Greasers - Interesting Reading For You Guys ?

Apple Roof Cleaning

Roof Cleaning Instructor
In my Patent search, I ran across this. http://www.wipo.int/pctdb/en/wo.jsp?IA=US1992009577&DISPLAY=DESC
Thought SOME may find it interesting ?
Maybe you guys have methods beyond this you use ?

WO/1993/010004) METHOD OF PREVENTING GREASE BUILDUP IN DUCTWORK Biblio. DataDescription Claims National PhaseNoticesDocuments Note: OCR Text
Note: Text based on automatic Optical
Character Recognition processes. Please
use the PDF version for legal matters WO 1993010004 19930527


METHOD OF PREVENTING GREASE BUILDUP IN DUCTWORK

Technical Field This invention relates to a method for preventing the adherence and ultimate buildup of grease and other grime in vent hoods and exhaust vent ductwork.

In particular, this invention is useful in preventing the buildup of grease and grime and facilitating in the removal of grease and grime from exhaust vent hoods as are commonly used in commercial and institutional kitchens. In commercial and institutional kitchens, it is necessary to vent fumes, smoke, etc., which are generated during the cooking process. Associated with these fumes an smoke are elements of grease and grime which are airborne solids or are volatilized until they contact the relatively colder surfaces of the hoods and vents. Also, certain amounts of grease and grime are also carried along as finel suspended particulate matter in smoke, etc.

Vent hoods and the associated ducts and fans must be kept clean or otherwise grease and grime which accumulates therein can buildup, increasing the danger of grease fires which can start in the hoods and vent ducts.

The cleaning out of these hoods and vent ducts is a difficult and laborious process, often requiring the physic scraping of the hoods and ductwork to remove the baked-on grease and associated grime or the use of very caustic materials along with high pressure power washing systems.

Summary of the Invention This invention relates to a method of preventing the buildup and associated grime in vent hoods and the associate ductwork by coating the ductwork and vent hoods with a thin film of a removable non-hygroscopic coating which also is repellent to the adherence of grease and which enables the vent hood and duct work to be cleaned using much less effor in some cases as simply as using an alkaline cleaner in a spray bottle with a wiping cloth.
Summary Disclosure of Invention The present invention relates to a method of preventing the buildup of grease and grime from vent hoods and ductwork

comprising coating the vent hoods and ductwork with a thin continuous removeable coating of a grease repelling composition comprising from about 2 to 17% by weight of a lo molecular weight alkali resin; from about 0.07 to 0.6% by weight of a temporary metal crosslinking agent selected from the group consisting of zinc oxide and zirconium oxide; sufficient ammonium hydroxide to substantially neutralize th resins; about 2 to 10% by weight of a coalescing solvent; about 3.5 to 13.5% by weight of a high molecular weight acrylic emulsion polymer; about 0.0015 to 0.15% by weight a fluorosurfactant selected from the group consisting of (RfCH2CH20)2 P(O) (ONH ) and mixtures of (RfCH2CH20) P(O) (ONH2) with a nonfluorinated surfactant where Rf is F(CF2CF2)n with n being a mixture of numbers from 3 to 8; and water.

Best Mode For Carrying Out the Invention As indicated previously, the process of maintaining vent hoods and associated ductwork in sufficiently clean condition to prevent or lessen the danger of fire in these hoods and exhaust ducts is a difficult and laborious process, often involving manual scraping of the built-up grease and grime from these hoods and vent work. This is obviously a highly labor intensive and arduous task which often is not done in commercial establishments leading to increased danger or risk of fire.

The present invention provides for a removable, temporary non-hygroscopic coating which is impermeable or substantially impermeable to the grease and grime preventing the adherence of these materials to the metal substrate of the hood and/or ductwork. In addition, the composition of the present invention is oil or grease repellent thereby further preventing the buildup of the grease and grime materials on the vent hoods and lengthening the time between which the vents hoods need be fully cleaned. If the compositions of the present invention were merely sacrificial removeable coatings without being grease and/or oil repellent, the vent hoods and ductwork would soon be coated to the same degree as in the past, the only difference being that the vent hood might be more easily cleaned

assuming that the person cleaning the vent hoods and ductwo is able to disrupt the film layer and thereby remove the grime and grease which has collected thereon.

In the present invention however, the thin continuous film is also grease and oil repellent thereby preventing substantial buildup of grease and grime in the hood and exhaust vent ductwork over the period of use and thus both extending the useful period between which the hoods and ven need be cleaned and facilitating the removal of the accumulated grease and grime from the hoods and ductwork wh cleaning becomes necessary.

Typically in commercial establishments, cleaning is do on a routine or periodic basis. The process of the present invention lends itself to this periodic maintenance approac since if the vent hood and ductwork is cleaned at intervals of every three months, the repellent properties of the film used in the method of the present invention are sufficient prevent substantial buildup thereby allowing the underlinin removable film to be easily disturbed carrying away with it any additional materials which have been deposited thereon. As noted above, it is very important that the films useable in the present invention be capable of providing a thin continuous film, which is also easily removeable and which is non-hygroscopic. If the film were not continuous, there would be areas of the vent hood and/or exhaust ducts which would be left exposed, creating difficulties for subsequent cleaning. Furthermore, since the exposed areas would not be repellent, the grease and grime would buildup these areas. Therefore, the composition should level reasonably well and should be easily applied by either wipi the composition onto the vent hood and exhaust ductwork or spraying the composition onto these surfaces. The films mu be non-hygroscopic because the environment in a cooking hoo and exhaust duct often will include steam or other water vapor. If the films are effected by ambient moisture, they will degrade over time and the protective effect will be lost.

The compositions which are useable in the methods of t present invention comprise seven components. The first

material in the composition of the present invention is a lo molecular weight alkali soluble acrylic resin. These acryli resins typically have a number average molecular weight of less than 3,000 and should be present in an amount of from 2 to 17% by weight in the composition.

Suitable resin materials include the following: 31% styrene, 37% alpha methyl styrene, 32% acrylic acid (31S/37AMS/32/AA) , 67% styrene, 33% acrylic acid (67S/33AA) ; 45% alpha methyl styrene, 30% ethyl acrylate; 25% acrylic acid (45AMS/30EA/25AA) ; 82% methyl ethacrylate, 18% methacrylic acid (82MMA/18MAA) and the like.

With regard to the amount of resins present in the composition useful in the method of the present invention, i has been found that from 2 to 17% of resin is necessary. Below about 2%, the film becomes discontinuous and does not wet-out properly on the metal surfaces of the vent hoods and ductwork. At amounts over the 17%, the film becomes too brittle and the overall film tends to loose water resistance. Water resistance is an important property of the ultimate films produced by the compositions of the present invention since during the cooking process in industrial, institutional and commercial establishments a substantial amount of moisture in the form of steam also is exhausted through the vent hoods. If these films were not water resistant, steam from cooking would attack the films making them more discontinuous and therefore less effective.

Typical resins suitable for use in the method of the present invention are low molecular weight materials, i.e., those resins with a weight average molecular weight (Mw) of less than 15,000 and preferably less than 10,000. At high molecular weights the resulting films become too brittle to be used.

Preferred amounts of the alkali soluble acrylic resins are from 4 to 9%. The preferred alkali soluble acrylic resin is 32S/32.9AA/35.1AMS.

The compositions useful in the method of the present invention also include from about 0.07 to 0.6% by weight of a metal temporary crosslinking agent selected from the group consisting of zinc oxide and zirconium oxide.

The activity of zirconium oxide and zinc oxides in bas compositions to perform crosslinks upon drying is well know and has been used for many years in the floor coating art. The preferred metal temporary crosslinking agent is zinc oxide which in combination with ammonium forms a zinc ammonium carbonate complex.

The compositions useful in the method of the present invention also include ammonium hydroxide as the base. Sufficient ammonium hydroxide must be present in the composition both to form to substantially neutralize the alkali soluble resin present and to assist the metal temporary crosslinking agent. The amounts of the ammonium hydroxide necessary to accomplish these tasks are well know in the art. Typically, from about 0.7 to about 6.25% by weight of ammonium hydroxide is preferred.

The compositions useful in the method of the present invention also include from about 2 to about 10% of a coalescing solvent. Suitable coalescing solvents include diethyl glycol monoethyl ether, dipropylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether and the like.

As noted above, the coalescing should be present in an amount of from 2 to 10% by weight. It is preferred to incorporate from 3 to 5% by weight of coalescing solvent. I the solvent composition is too high, the films will take too long to dry to be used effectively. Also the film will tend to be gummy and sticky. If the composition includes too little coalescing .solvent, the films will powder or stress crack and will not properly repel the grease and other materials.

The compositions suitable for use in the method of the present invention also include from about 3.5 to 13.5% by weight of a high molecular weight acrylic emulsion polymer. These emulsion polymers can be made by any conventional emulsion polymerization process. Suitable emulsion polymers include styrene, alphamethyl styrene, methyl methacrylate, butyl aerylate, methacrylic acid, and 2-ethylhexylacrylate a monomers. Typical monomer compositions include 43% methyl methacrylate, 48% butyl acrylate, 9% methacrylic acid

There is a LOT more, but it will not post in one thread
I will come back and post the link http://www.wipo.int/pctdb/en/wo.jsp?IA=US1992009577&DISPLAY=DESC
 
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