1. Field of the Invention
This invention relates to multi-component dispensing and mixing systems for paints and coatings. More particularly, the present invention relates to devices and methods for packaging, mixing, and dispensing multi-component paints.
2. Related Art
U.S. Pat. No. 5,249,709 discloses cartridges for dispensing reactive materials in predetermined ratios. U.S. Pat. No. 5,072,862 discloses static flow mixers for use in dual cartridges, U.S. Pat. No. 4,538,920 discloses a dual cartridge with a static mixer in the nozzle. U.S. Pat. No. 4,767,026 discloses dual cartridge dispensing and mixing apparatus. U.S. Pat. No. 6,135,631 discloses a static mixer and nozzle for a multiple component dispensing cartridge having at least two cylinders. U.S. Pat. No. 5,535,922 discloses a caulking gun dispenser device, which allows one to use a multi-component cartridge dispenser in a regular caulking gun. U.S. Pat. No. 5,875,928 discloses a two-plunger dispensing gun suitable for mixing and discharging two-component compositions. U.S. Pat. No. 6,244,740 discloses a mixer for multi-component cartridges. U.S. Pat. No. 3,166,221 discloses a plastic, double-tube dispensing container. U.S. Pat. No. 3,828,980 discloses a dual cartridge dispenser. U.S. Pat. No. 6,601,782 discloses a disposable spray nozzle assembly.
The use of high solids coatings is becoming increasingly popular. In the 1970's, regulatory bodies such as the Environmental Protection Agency (EPA) and the California Air Resource Board (CARB) began to scrutinize the paint and coating industries to reduce the amount of Volatile Organic Compounds (VOCs) released into the atmosphere. The regulatory bodies discovered that the solvents contained within paints were contributors to air pollution. The VOCs, which are released as the solvent evaporates from a painted surface during cure, react with nitrogen oxides to form ozone. As a result, the Clean Air Act (CAA) was developed by the EPA to regulate policies concerning the release of large amounts of VOCs into the atmosphere in an attempt to prevent further damage to the environment.
Each year coating application regulations reduce the amount of allowable VOC emissions released from coatings into the atmosphere. The military has begun specifying traditional solvent-based coatings and high solids, edge retentive coatings for construction and repair. These coatings were the government's solution to service life extension and reduced life cycle cost goals while at the same time addressing the tightening regulations. However, with the introduction of this new coating technology, new processes and handling requirements, unfamiliar to painters, were also introduced.
Multi-component, high solids paints cure by a chemical reaction that creates heat after mixing. With the small amount of solvent content, VOCs are greatly reduced, and the coatings provide a higher level of performance. These types of coatings have a much higher viscosity than traditional solvent-based systems, making them very difficult to apply. If the coatings are manually mixed and applied, the pot life of the mixture is shortened dramatically, often as short as 30 minutes and some measured on the order of seconds. Application environment and ratio control have more effect on these coatings than traditional coatings. Pot life, viscosity and curability are all dependent at least in part on temperature and humidity. Painters and supervisors need to continuously monitor these variables to produce the best product, which leads to increased costs.
The present invention solves the above problems, and others.
One embodiment of the present invention provides a device for applying a coating, which includes:
a multi-component cartridge,
a static mixing nozzle in fluid communication with the cartridge, and
at least one paint applicator selected from the group including a roller, a
brush, and an angled spray tip, in fluid communication with the nozzle.
Another embodiment of the invention provides a method, which includes applying a coating to a surface with the above-described device.
Another embodiment of the invention provides a method, which includes applying a non-skid coating to a surface with the above-described device.
The following description will be better understood when read in conjunction with the appended drawings. For the purpose of illustrating the invention, there is shown in the drawings some embodiments which are presently preferred, it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.
Various other objects, features, and attendant advantages of the present invention will be more fully appreciated as the same becomes better understood from the following detailed description of the invention, which is not intended to be limiting unless otherwise indicated.
The invention provides a multi-component industrial paint packaging system for use in simultaneously dispensing, mixing, brushing, rolling or spraying liquid coatings in one easy step. Preferably, the coatings are multi-component, reactive, high-solids low-VOC paints. More preferably, the coatings are multi-component, reactive, high-solids low-VOC marine, military, and industrial paints. The present invention desirably allows one to dispense, mix, roll, or spray two component marine and industrial paints in one continuous step without having to pre-mix either component. It also allows dispensing of the exact amount of marine, military, and industrial paints while reducing or eliminating the mixer's or painter's exposure to unnecessary hazardous materials, reduces the amount of hazardous waste in application, disposal and clean up, and reduces the amount of VOC's released into the environment. The invention is particularly suitable for large-scale industrial applications because it enables significant and unexpected savings of both material and labor, which translates into significant cost savings. The invention eliminates the need for packaging paints in one and five gallon cans, eliminates the need to open and premix paints, eliminates the need to manually pre-measure paints into exact ratios for use, significantly reduces waste and generation of excess paint associated with conventional methods, and provides a direct delivery method for marine and industrial paint by rolling, brushing, spraying, or power rolling the paint onto the surface to be painted. For example, in the course of industrial or commercial painting on a large scale, the paint composition is often continually transferred from large containers to smaller containers to avoid mixing more paint than needed and to reduce the carry burden of the individual painter.
In this embodiment, a manual dispensing gun 2 is shown. During operation, piston rods 3 attached to piston plates 3a exert a force sufficient to push the piston plates 3a and cartridge piston seals 4, 4a simultaneously through the multi-component cylindrical cartridges 1, 1a, which force ejects their respective contents, the reactive components. The reactive paint components flow through a common discharge nozzle 8 and into the static mixing nozzle 9, where they contact one another. The reactive components are intimately mixed with one another as they flow through the static mixing nozzle 9.
In this embodiment, manual dispensing is initiated and controlled by a trigger system 5. The dispensing gun optionally has a handle 2a for the user to hold onto the dispenser while rolling the coating onto the work surface. The mixed paint is fed from the static mixing nozzle 9 into a discharge tube 10 that feeds the mixed coating material into the roller 7 for direct application to the work piece. The manual dispensing gun 2 has a support arm 6 attached to it, which supports the roller attachment 7.
The reactive components are ejected from their respective cartridges into the static mixing nozzle 9 in a ratio determined by the respective cross-sectional areas of the cartridges I and I a. In this way, the reactive components are thoroughly mixed and in the correct proportion, and thus two sources of potential error are avoided, in contrast with conventional mixing and formulating procedures. In addition, in one preferred embodiment, any or all of the roller 7, static mixer 9, and discharge tube 10 are disposable, being the only components that contact the mixed paint, so time-consuming and wasteful solvent cleaning is not necessary. The cartridges I and I a may either be resealed for future use if some remains or, if none remains, they may be disposed of as well.
Another preferred embodiment of the present invention is illustrated in
The twin hoses 12 attach to a coupler 15. The coupler 15 has a securing nut 16 to attach it and thus the hoses 12 to the remote roller applicator 17. The length of the hoses 12 may vary according to need. The remote roller applicator 17 has a trigger 18 that allows an operator to activate the pumps 13 and dispense and apply the mixed paint on demand and as needed. In the remote roller applicator, the reactive paint components are mixed in the static mixer 9, and the thus-mixed paint proceeds, still under pressure from the pumps 13, into a discharge tube 10 and to the roller 7 for direct application to the workpiece. The remote roller applicator 17 includes a support arm 6 supports the roller 7 in place during application. Preferably, the roller 7, discharge tube 10, and static mixer are each independently removable and/or disposable.
One preferred embodiment is illustrated in
One preferred spray tip 21 is available from V.O. Baker, Spray Tip Nozzle Manifold Part No. SPRYNZZL004-VOB. An angled spray tip 21 is preferred in view of reaching hard-to-access areas such as stiffeners near the hull of a ship. Such spray tips have an angle between the spray direction and the paint feed direction. Preferable angles range from 15 to 90 degrees and include 15, 25, 35, 45, 55, 60, 75, 85 and 90 degrees. The spray tip 21 may attach to the nozzle by any conventional fluid connection including Luhr-Lock, Bayonet, screw on, retaining nut, snap fit, friction fit, and the like. Friction fit is preferred.
In one embodiment of the invention, a flexible hose connects the spray tip 21 and the static mixer nozzle 9. In such an embodiment, the hose 22 remains attached to the spray tip 21, but is suitably lengthened to accommodate the length of the flexible hose between the spray tip 21 and the static mixer nozzle 9. In this embodiment, either a manual dispensing gun 2 or a pneumatic or hydraulic dispensing gun 38 may be used, and the remote spray applicator gun 20 may also be used. The operator may easily hold the spray tip 21, the flexible hose, and the hose 22 in one hand for paint application, and may initiate and control the liquid coating flow with the remote spray applicator gun 20 in the other. In this embodiment, the spray tip 21 may or may not be angled. This desirably allows the painter nearly complete freedom of movement, in contrast with bulky and awkward conventional application techniques. Heretofore, such freedom of movement and ability to spray apply was unknown. The flexible hose may have any length so long as the dwell time of the mixed paint in the flexible hose does not exceed the pot life. This flexible hose may be suitably disposable.
The mixed paint may be applied from the static mixing nozzle onto an outer surface of the brush bristles, or the mixed paint may be applied to an interior portion of the brush bristles via one or more hollow passages leading from the outlet of the static mixing nozzle through the body of the brush 23 and into the interior part of the bristles. In the present context, either alternative is considered to be a fluid connection. The latter alternative, using one or more hollow passages through the brush 23, is preferred. The brush 23 and static mixing nozzle 9 are each independently removable and/or disposable.
In the context of the present invention, both the power roller type assembly using a perforated roller and the roller coater type assembly, such as described herein, are considered fluid connections. The former alternative, using the power roller assembly, is preferred.
In operation, removal disc 35 and nose plug 32 are removed, providing an unobstructed passage for the reactive components from reservoirs 26 and 27 though apertures 28 and 29 and discharge nozzle 8. The static mixer nozzle is attached to the discharge nozzle 8. The reactive paint components are forced from reservoirs 26 and 27 and through apertures 28 and 29 by the movement of cartridge piston seals 4 and 4a, which are sealingly and slidably disposed within the reservoirs 26 and 27. The ejection of the components is accomplished by the use of a pneumatic or hydraulic dispensing gun 38 or a manual dispensing gun 2.
The piston plug 39 sometimes known as a bleeding pin or a burping pin is optionally present in the cartridge piston seals 4, 4a and is useful when bleeding gas or air out of the reservoirs 26 and 27 when they are filled with reactive component liquids such as paint, resin, or catalyst, for example.
The multi-component cartridge 1 and 1a is not particularly limiting. Suitable cartridges are described, for example, in U.S. Pat. No. 5,249,709. Other suitable cartridges may be obtained commercially from Plas-Pak Industries, Norwich Conn. The cartridges 1 and 1a may either have a side-by-side construction, or a cartridge-within-a-cartridge construction. Examples of the latter are disclosed in, e.g., U.S. Pat. No. 5,310,091.
The respective cartridges 1 and 1a may have a permanent connection between them, or they may be separable, for example by one or more snap or similar connections. In one embodiment, the cartridges 1 and 1a are connected to one another by a snap connection near the common discharge nozzle 8. The cartridges 1 and 1a may be made of any suitable material, such as polyethylene or nylon. Nylon is preferred. Individual reservoir 26 and 27 volumes in the cartridges 1 and 1a may each independently range from 50 to 3000 ml, which range includes 50, 75, 100, 150, 250, 500, 750, 1000, 1250, 1500, 1750, 2000, 2250, 2500, 2750, and 3000 ml, and any combination thereof.
The reservoirs 26 and 27 in the cartridges may each independently have any suitable cross sectional area, in accordance with the formulation requirements of the reactive components. The cross sectional area ratio may range from 1:1 to 1:20, which range includes 1: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 as appropriate. Ratios of 1:1, 1:2, 1:4 are preferred.
The present invention is particularly useful for applying liquid coatings such as reactive two-component solvent-based coatings, edge-retention coatings, anti-corrosive coatings, high-solids coatings, low VOC coatings, Chemical Agent Resistant Coatings (C.A.R.C. paints), non-skid coatings, and the like, including but not limited to topcoat and/or primer coatings of polyurea, polyaspartic, epoxy, acrylic, silicone, polyester, polyurethane, polyamide, bisphenol A epoxy, bisphenol F epoxy, epoxy-polyamide, epoxy-polyamine, epoxy-ketamine, non-skid, aggregate-containing, aluminum oxide-containing, silica-containing, and the like.
These coatings are suitable in a variety of marine, military, off shore, petrochemical, automotive, transportation, rail, aerospace, and industrial applications. Other suitable application examples include without limitation ship construction and repair of tanks, ship structure, weapon systems, military transport vehicles, weapons, missiles, rail car repair, industrial transpiration equipments, pleasure craft and commercial ship construction and repair, aerospace systems, off shore platforms and markings, airplane maintenance, facilities and structures, industrial machinery and equipments, lawn and garden equipments, rigid container and closure coatings, and food processing equipment coatings. Marine and military applications are preferred.
The coating compositions are supplied as two or more separate components, usually referred to as the base and the curing agent. When these components are mixed, immediately before use, a chemical reaction occurs. These materials therefore have a limited ‘pot life’ before which the mixed coating must be applied. The polymerization reaction continues after the paint has been applied and after the solvent has evaporated to produce a densely cross linked film which can be very hard and has good solvent, mechanical, and chemical resistance. There are also chemically resistant paints often referred to as blast primers, shop primers, temporary primers, holding primers, and the like. These types of primers are more preferably used on structural steelwork, immediately after blast cleaning, to maintain the reactive blast cleaned surface in a rust free condition until final painting can be undertaken.
The reactive components, for example, resin and catalyst, or base and curing agent as more commonly referred to, may be formulated in proportions known to those of skill in the art. Preferred coatings include bisphenol A epoxies and bisphenol F epoxies, with one or more polyamide, polyamine, and ketamine being preferred as catalyst. Preferred curing agent: base ratios range from 1:1 to 1:20, with 1:1, 1:2, 1:3 and 1:4 being preferred.
High-solids, low solvent or low VOC coating compositions have solids content approaching 100% by weight of the coating. The solids content ranges from more than 80% to 100% by weight, which includes 85, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 99.5, less than 100, and 100% by weight. The VOC or solvent content approaches zero, ranging from typically less than 20% by volume to zero percent, which includes 19, 17, 15, 13, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, greater than zero, and zero percent by volume. Coatings having zero to 6% VOC's by volume are preferred. Coatings having 94 to 100% solids by weight are preferred.
The present invention is also suitable for high-VOC coatings, having solvent contents of 50 to 94% solids by weight. This range includes 50, 55, 60, 62, 64, 66, 68, 70, 75, 80, 85, 90, and 94% solids by weight. These types of coatings are particularly suited for application to antennas, specialty coatings, and the like. A preferred example of such high-VOC liquid coatings is MIL-DTL-24441.
The preferred coating compositions have short pot lives upon mixing the reactive components, ranging from 3 hours or less to 0.25 hours, which range includes 2.75, 2.5, 2.25, 2, 1.75, 1.5, 1.25, 1, 0.75, 0.5, and 0.25 hours.
One or more than one coat may be applied. The coating compositions may contain one or more pigments, inhibitive agents and/or pigments, and non-inhibitive agents and/or pigments, microballoons, and the like.
One embodiment of the present invention provides a method of applying a non-skid coating composition, which includes applying to a surface an epoxy composition that contains an aggregate, such as aluminum oxide or silica, with the paint dispensing system described herein. In this embodiment, one of the cartridges 1 and 1a contains a hardener, and the other contains an epoxy resin and the aggregate. The reactive hardener and epoxy resin with the aggregate are combined and mixed in the static mixer nozzle 9, and applied. A desirably tough non-skid surface results.
In another embodiment of the invention, a one component composition is applied using the paint dispensing system described herein. In this embodiment, a reactive two component paint is not used, and instead a one-component composition is contained in both cartridges. This embodiment provides the ability to produces a superior conventional coating from a convenient packaging system, and reduces waste and cleanup.
One embodiment of the invention includes a cartridge 1, 1a that optionally has hermetically sealed dispensing and/or filling ends to prevent marine and industrial paints from leaking during handling, shipping and storage. The hermetic seal may be foil, plastic, or a combination thereof. Preferably, the hermetic sealing material is chemical resistant and forms a gas and liquid tight seal on either or both of the filling ends 25 (after being filled with one reactive liquid of the multi-component coating, cartridge piston seals 4, 4a, inserted, and degassed through piston plugs 39) and the aperture end 28, 29 of the multi-component cartridges. The hermetic seals at the aperture end of the cartridge may complement or replace the removal disc 35 and nose plug 32 if desired.
Static mixing nozzles 9 are not particularly limited so long as they progressively divide and recombine to thoroughly mix the reactive components of the coating. As the reactive components traverse the length of the static mixing nozzle 9, the number of mixing “folds” experienced by the fluid may be calculated as 2, wherein n is the number of mixing elements present. Some examples of static mixing nozzles 9 are described, for example, in U.S. Pat. Nos. 4,850,705, 4,767,026, and 4,538,920. Suitable static mixers may also be obtained commercially from Plas-Pak Industries, Norwich Conn.; and V.O. Baker Co., Mentor Oreg. The size of the static mixing nozzles 9 may suitably range from ⅛″ to 1½″ or 1 to 25 mm as appropriate, which includes ⅛″, 3/16″, ¼″, 5/16″, ⅜″, 7/16″, ½″, 9/16″, ⅝″, 1 1/16″, ¾″, 13/16″, ⅞″, 15/16″, 1″, 1¼″, 1½″ and any combination thereof. Preferably, a step-down static mixer is used, wherein the I.D. changes from ⅜″ to ¼″ as one nears the outlet. Such step-down static mixing nozzles are available from Plas-Pak Industries, Norwich Conn. The static mixing nozzle 9 may attach to the common discharge nozzle 8 on the cartridges 1 and 1a with any suitable connection such as screw threads, Luhr-lock, lock-on retainer nut, bayonet tip, snap fit, frictional fit, and the like.
The dispensing gun is not particularly limited so long as it is capable of applying sufficient force to the cartridge piston seals 4 and 4a to move the reactant components from their respective cartridges 1 and 1a through the static mixing nozzle 9 and on to the applicator roller 7, sprayer 21, or brush 23. The dispensing gun may be of the manual type 2, or the pneumatic or hydraulic type 38. The manual type may apply force through a clutch bar, screw, ratchet or similar mechanism connected to the squeeze trigger and handle assembly 5. One suitable manual dispensing gun is the NEWBORN 530™, manufactured by Newborn Bros. Other suitable manual guns are described, for example, in U.S. Pat. No. 5,875,928. The pneumatic type of dispensing gun is preferably regulated and air driven. Preferred pneumatic systems include the HSS™ by Plas-Pak Industries, Norwich Conn. Both manual and pneumatic dispensing guns are available, for example from V.O. Baker Co., Mentor Ohio. Hydraulic dispensing systems may suitably operate at pressures on the order of 800 psi.
The roller attachment 7 preferably includes a perforated or bleed through roller core and/or cover. Non-limiting examples of suitable perforated roller covers are available, for example, from Hennes-Johnson Equipment Co., Prague Minn.; and Wagner Spray Tech Corporation, Minneapolis Minn. For the roller coater embodiment, any roller 7 suitable for the paint may be used, including perforated roller cores and covers.
One preferred embodiment of the present invention provides a system that packages marine, military, and industrial multi-component reactive liquid paints in cartridges for dispensing and direct rolling or spraying paints by manual, pneumatic, or hydraulic methods.
Another method of the present invention provides a method for applying a high-solids, low VOC marine or military paint, to a surface using a multi-component cartridge.
The current system is particularly suitable for use in dispensing and applying multi-component coating systems, marine and military paints. Just dispensing the components in the correct proportions is insufficient. When dispensed, the components must be mixed to activate the curing process. As stated previously, however, manual mixing has certain drawbacks. The present invention provides a means of storing, dispensing, mixing, and applying reactive multi-component paints at or near point of use, conveniently, safely and with significantly reduced waste and improved coating performance. In this manner any amount of paint can be prepared for use, from very small amounts to large amounts. This avoids waste and provides a system for providing just the right amount of prepared paint for the time available for application.
The present invention desirably reduces the problems encountered with multi-component, reactive and high-solids paints. These include the problems of hot potting, inaccurate proportioning, mixing, and human error. The present invention increases the ease of coating application for painters to apply coatings. In addition, because the coating reactants remain sealed until mixed and applied, it is safer for the painters as it reduces their exposure to often toxic reactants, such as curing catalysts, isocyanates, and the like. In addition, the present invention results in a more manageable process on an industrial scale, it drastically reduces paint can change out time, waste due to expired pot life and spillage, and clean-up solvent. The present invention is particularly suitable for marine and military paint multi-component paints.
In accordance with the present invention, preloaded disposable paint cartridges with disposable static mixers keep the base and hardener separate from one another as long as possible and allow dispensing of paint on demand. A preloaded disposable paint cartridge with disposable static mixer is used to mix the multi-component systems as close to the cartridge as possible. The use of preloaded disposable paint cartridges with disposable static mixers eliminates pot life problems and viscosity problems that result in waste and application difficulties.
Preloaded disposable military and marine paint cartridges with disposable static mixers reduce the problems encountered with viscosity and pot life by keeping the two components separate as long as possible. Keeping the reactive components of multi-component coatings separate eliminates the risk of the coatings curing before use. Components are mixed at the work site when needed. This not only reduces the amount mixed and waste generated, it improves product integrity by maintaining exact ratios, thereby allowing the end user to achieve maximum service life expectancy.
Military and marine coatings are much more sensitive than traditional solvent based epoxies and coatings. In the present application, marine and military paints are especially formulated to be used in a saltwater marine environment and/or are specified by the U.S. military, such as the U.S Army, Navy, Marine Corps, Air Force, Military Sealift Command, and/or Coast Guard. These coatings must be mixed properly and thoroughly according to manufacturers specifications in order to cure. High solids coatings, and particularly those for marine and military applications, have specific mix ratios with very tight tolerances, generally plus or minus 3%. There are many different factors that affect whether a coating will be on or off ratio. In accordance with the present invention, preloaded disposable military and marine paint cartridges with disposable static mixers assures the mix ratios are maintained when dispensing. In accordance with one embodiment of the present invention, these dispensing systems are combined with a paint roller or brushing apparatus and method. In accordance with another embodiment of the present invention, a multi-component cartridge preloaded with one or more reactive components of a high solids, low VOC marine and military paint.
The entire contents of each of the references, patents, and patent applications cited herein is hereby incorporated by reference, the same as if set forth at length.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically recited herein.
This application is a divisional of U.S. Ser. No. 12/897,362, filed Oct. 4, 2010, which is a continuation of U.S. Ser. No. 11/563,791, filed Nov. 28, 2006, now U.S. Pat. No. 7,815,384, which is a continuation of U.S. Ser. No. 11/003,449, filed Dec. 6, 2004, now U.S. Pat. No. 7,144,170, which claims priority to U.S. Provisional Application Ser. Nos. 60/551,200, filed Mar. 8, 2004 and 60/533,973, filed Jan. 2, 2004, the entire contents of each of which are hereby incorporated by reference.
Number | Date | Country | |
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60551200 | Mar 2004 | US | |
60533973 | Jan 2004 | US |
Number | Date | Country | |
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Parent | 12897362 | Oct 2010 | US |
Child | 14194193 | US |
Number | Date | Country | |
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Parent | 11563791 | Nov 2006 | US |
Child | 12897362 | US | |
Parent | 11003449 | Dec 2004 | US |
Child | 11563791 | US |