WO2015105743A1

WO2015105743A1 - Fluorinated carbon based polymer in paste wax composition

Info

Publication number: WO2015105743A1
Application number: PCT/US2015/010103
Authority: WO
Inventors: Eve Fabrizio; Patricia Mcclarren
Original assignee: Johnson Controls Technology Company
Priority date: 2014-01-07
Filing date: 2015-01-05
Publication date: 2015-07-16

Abstract

A polytetrafluoroethylene (PTFE)-wax blend release agent composition includes 5 - 50 weight % fluorocarbon based polymer and 50 - 95 weight % paste wax and preferably 5 - 40 weight % fluorocarbon based polymer and 60 - 95 weight % paste wax and more preferably 8 - 15 weight % fluorocarbon based polymer and 85 - 92 weight % paste wax. The fluorocarbon based polymer may be polytetrafluoroethylene (PTFE). A polyurethane foam object production method is provided in which the fluorocarbon based polymer -wax blend release agent composition is applied to at least one mold tool. A polyurethane foam object production system is provided that includes a mold tool and a layer of the fluorocarbon based polymer -wax blend release agent composition.

Description

FLUORINATED CARBON BASED POLYMER IN PASTE WAX

COMPOSITION

FIELD OF THE INVENTION

[0001] The present invention relates to paste wax compositions and more particularly to paste wax compositions applied to molding tools for polyurethane foam object production as well as a polyurethane foam object production system and method of polyurethane foam object production involving paste wax compositions applied to molding tools of a mold.

BACKGROUND OF THE INVENTION

[0002] Flexible and semi-flexible polyurethane foams are used extensively for interior components of motor vehicles, such as in seats, headrests, armrests, roof liners, dashboards and instrument panels. Polyurethanes are used to make motor vehicle seats in which molds for each seat type are provided. The mold may be a closeable structure that allows casting of a molded flexible foam object for the seat cushion.

[0003] Polyurethanes are a general class of polymers in which organic repeating units are joined by carbamate and urea linkages. Polyurethanes are typically produced by reactions in which a polyol having two or more hydroxyl groups are reacted with a polyisocyanate having two or more isocyanate groups. The hydroxyl groups and isocyanate groups may react with one another in a one-to-one ratio to form carbamate and urea linkages, and in certain configurations, the relationship can be as wide ranging as from as low as about 0.6 up to approximately 1.3. This ratio of hydroxyl groups to isocyanate groups is commonly referred to as reaction index within the art. To facilitate these polymerization reactions, the reaction materials may be heated and, alternatively or additionally, a catalyst may be provided.

[0004] Polyurethanes have a wide variety of molded uses, including foam seating, foam padding, sealants, gaskets, and so on. The end use of a given polyurethane is dependant on the particular starting materials reacted to produce the polyurethane (e.g., the molecular structure of the polyol and/or polyisocyanate), and the conditions under which the starting materials are reacted. For instance, polyurethane foam products, and in particular foam seating, foam paneling, and other shaped polyurethane foams, are often produced inside of a mold cavity having a shape corresponding to a desired shape of the foam.

[0005] To produce the polyurethane foam inside of the mold cavity, the materials of a foam formulation, which includes an unreacted mixture of polyol and polyisocyanate, are dispensed into the mold. The mixture then reacts, for example after the mixture is heated. During the reaction, the polyurethane mixture foams and expands to fill the interior of the mold cavity, thereby assuming the shape of the cavity. Additional materials may be provided to enhance foaming of the mixture. For example, water may be used as one type of many different blowing agents to allow the urethane mixture to fill the mold cavity. Water, which is the most environmentally friendly blowing agent, reacts with the polymer and polymerization components to create carbon dioxide and urea. The foam chemistry is allowed to react within the mold cavity. Once the foam reacts, the foam object (e.g., a seat cushion) may be removed from the mold and used (e.g., within a seat) after a cure time. The shorter the cure time, the better for manufacturing time and costs. [0006] The foam production cycle includes dispensing un-reacted foam material formulation for manufacturing polyurethane into a mold cavity of a tool; and reacting the formulation in the mold cavity to form the open cell, molded polyurethane foam object having a shape corresponding to the geometry of the mold cavity. [0007] The mold cavity may be coated with a mold release agent to facilitate release of the foam object from surfaces of the mold tool and removal of the foam object from the mold cavity. Typical mold release agents include release agents that are commonly applied through spray or manual wipe-on operations to the surface of the mold cavity before each foam production process is performed (e.g., before each foam object is molded). Generally, the release agents are replenished after every foam production cycle because a significant amount of the release agents are lost to the foam. Paste wax is a release agent that has been used to form a base barrier between the foam material and the mold cavity surfaces. Spray applied mold release agents are commonly applied to the surface of the mold cavity for each production cycle on top of the paste wax barrier. [0008] PTFE (polytetrafluoroethylene) is known for its release properties and has been used in many applications.

[0009] German Democratic Republic (GDR) patent publications: DD101 595; DD103

188; DD 106 410; DD 113 715; DD 119 956; DD 131 732 and DD 139 808 describe mold release agents for the production of polyurethane moldings. DD 131 732 discloses such a release agent, for the production of polyurethane moldings, for hood mold release without the foam structure being disturbed. The release agent is a mixture of 1 to 40 parts of hard and high melting hydrocarbon waxes with other components to achieve a solidification point above 70 ° C and other attributes. DD 131 732 also refers to the use of release agents in polyurethane processing such as pastes, solutions, suspensions or emulsions, that might comprise active components like silicone, PTFE, natural or synthetic wax, salt of fatty acids, fatty acid ester or fatty acid amide. DD 139 808 describes release coating compositions for the processing of polyurethane foams, wherein the release film adheres on the polyurethane surface and is anchored thereto. DD 139 808 also mentions that forms of silicone rubber or polytetrafluoroethylene were known that facilitate coatings or so-called internal release agents, but that these present difficulties that have not been resolved.

[0010] US 2009/0036619 Al (corresponding to DE 10 2007 036 792 Al) describes a polypropylene wax that may be used as release agent for plastic processing. The wax has a high melting point. The melt viscosity acc. DIN 53019 at 170°C may be in the range of 20 mPas to 30000 mPas, with DSC melting points between 158°C and 161°C. In general such wax is hard and brittle and might be provided as a powder but, if mixed with other types of wax or paraffin, the release agent might have different mechanical properties. It is mentioned that the waxes can be comminuted and employed both in pure form and in admixture with waxes of another type, e.g. amide waxes, nonpolar or polar polyolefin waxes not based on metallocenes, montan or Carnauba waxes, paraffins such as Fischer-Tropsch paraffins or further components such as PTFE (polytetrafiuoroethylene).

[0011] U.S. 6,245,722 discloses a lubricant that includes a silicone wax that has been dissolved in solvent, emulsified or suspended in an inert carrier. The lubricant repels water and sheds dirt and may be used for lubricating the solid surfaces of moving parts. The lubricant is particularly useful for lubricating high performance products that are used in a dirty environment. In one preferred embodiment, the lubricant includes methyl stearoxy dimethicone wax that makes up about 11% by weight, a microcrystalline wax having a melting point of about 69°C. and makes up about 11% by weight, hexane as the volatile solvent which makes up about 65% by weight, and insoluble PTFE particles which make up about 0.2% by weight of the lubricant.

[0012] U.S. 6,114,448 discloses a composition with a substantially homogeneous semi-solid intimate mixture of (I) over 85% by weight of finely divided particles of at least one fluoropolymer (such as PTFE) and (ii) less than 15% by weight of at least one normally liquid polysiloxane. This provides a semi-solid wax-like composition and a liquid waxy composition that can be used to reduce the friction properties of a variety of substrate materials.

[0013] U.S. 4,849,264 discloses a coating composition for application to a metal part, which improves corrosion resistance and significantly reduces the co-efficient of friction of the surface of the part and a one coating step method for applying the coating to form two distinct layers on the coated part. The composition includes an oil phase in which

polytetrafluoroethelene particles are suspended mixed with a resin film forming paint composition. Upon applying the coating to the part and curing of the resin film, the oil phase separates and forms an overlayer of oil having the polytetrafluoroethelene particles uniformly distributed in the oil layer.

SUMMARY OF THE INVENTION

[0014] The invention provides a release composition for polyurethane foam object production that results in a reduction and/or elimination of the need to apply spray mold release, to mold tools of a mold, for each round of production. The invention also provides a polyurethane foam object production system that includes a fluorocarbon based polymer (such as polytetrafluoroethylene, fluorinated polypropylene, fluorinated ethylene, fluorinated silicone and other fluoropolymers), particularly PTFE (polytetrafluoroethylene), in paste wax composition. Further, the invention also provides a polyurethane foam object production method that includes applying the fluorocarbon based polymer in paste wax composition of the invention to a mold surface.

[0015] According to the invention, a fluorocarbon based polymer material, such as

PTFE particles, is blended with liquified paste wax at a concentration of 5 - 50 weight % fluorocarbon based polymer particles with 50 - 95 weight % paste wax and preferably 5 - 40 weight % fluorocarbon based polymer particles with 60 - 95 weight % paste wax and more preferably 8-15 weight % fluorocarbon based polymer particles with 85 - 92 weight % paste wax to create a fluorocarbon based polymer- wax blend. The blend is then allowed to cool back to solid form. A preferred composition is a PTFE in paste wax composition according to the invention that is 50 - 95 weight % basic paste wax composition and preferably 60 - 95 weight % basic paste wax composition and more preferably 85 - 92 weight % paste wax basic composition and 5 - 50 weight % PTFE and preferably 5 - 40 weight % PTFE and more preferably 8-15 weight % PTFE.

[0016] Other fluorocarbon based polymer in paste wax release agent compositions in the range of 5-50 weight % fluorocarbon based polymer and 50 - 95 weight %, paste wax basic composition may be provided according to the invention. Fluorocarbon based polymer in paste wax release agent compositions with fluorocarbon based polymer in the range of 5 - 40 weight % and paste wax basic composition in the range of 60 weight % - 95 weight % are preferred. A fluorocarbon based polymer content of 40 weight % or less is preferred.

Fluorocarbon based polymer in paste wax release agent compositions with fluorocarbon based polymer in the range of 8 - 15 weight % and paste wax basic composition in the range of 85 - 92 weight % are particularly preferred. The paste wax basic composition of hydrocarbon naptha and release blend is heated to a temperature to liquify the paste wax basic composition. Using a standard laboratory mixer, fluorocarbon based polymer material, such as PTFE particles with a particle size of 1 um, is mixed into the liquid paste wax basic composition to form a fluorocarbon based polymer in paste wax mixture of about 8 - 15 weight %

fluorocarbon based polymer, and 85- 92 weight % paste wax basic composition that comprises 58-72 weight % hydrocarbon naphtha and 28-42 weight % release blend.

[0017] According to another aspect of the invention, a polyure thane foam object production method is provided including preparing a molding tool. A release agent comprising the fluorocarbon based polymer in paste wax composition is applied to the molding tool(s).

[0018] The fluorocarbon based polymer material, such as PTFE particles, within the wax moves into available pores and fissures on the molding surface of the molding tool(s). This results in the fluorocarbon based polymer material virtually plugging the pores and fissures, allowing less holding action of the polyurethane molded part by the molding tool(s). This enables the production of multiple polyurethane molded parts before a release agent must again be applied to the tool.

[0019] The paste wax aids in movement of the fluorocarbon based polymer (such as

PTFE particles) into pores and fissures as it liquefies during the application process. The result is the ability to produce multiple molded polyurethane samples with no change to the production process required.

[0020] The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a schematic illustration of an embodiment of a foam object production system in which a foam formulation is provided to a mold cavity with a coating that includes the fluorocarbon based polymer in paste wax composition of the invention to produce a foam object; and

[0022] FIG. 2 is a chart showing a number of releases achieved for various PTFE and paste wax mixtures. DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Referring to the drawings, FIG. 1 is a schematic overview of a system 10 for preparing a foam object 12 (e.g., a polyurethane seat cushion) within a mold 14. The mold 14 includes a lid or first mold tool piece 20 and a bowl or second mold tool piece 22. The mold 14 may have only the lid and bowl, or may optionally have additional tool pieces which come together to form a molding cavity 18. The tool pieces 20 and 22 are constructed from base material 16. The molding cavity 18 is formed between first and second mold tool pieces 20 and 22. The mold cavity 18 is configured to shape the foam object 12 as the foam is produced. That is, the geometry of the mold cavity 18 may determine the shape of the foam object 12 during production thereof. [0024] The base material 16 may include any material, such as a metal (e.g., aluminum, steel, nickel, or other alloyed metals), an epoxy, a composite (e.g., a polymer matrix and a filler disposed within the polymer matrix), or similar materials that are capable of providing mechanical stability and other desired properties for the foam produced within the cavity 18. In some embodiments, the base material 16 may be selected so as to allow energy (^e-g-_> heat, light) to be imparted from an outside source to the polymerization reaction performed within the mold cavity 18. For example, the base material 16 may have a heat transfer coefficient suitable for conducting thermal energy to the mold cavity 18, and/or may be transparent to certain wavelengths of light (e.g., IR, UV) to enable energy to be deposited into materials disposed within the mold cavity 18.

[0025] The mold cavity 18, which is shaped to form the foamed object 12, is defined by the first and second mold tool piece 20, 22, each of which have an inner surface 24.

However, it should be noted that in other embodiments, the mold cavity 18 may be formed from a single piece, or more than two pieces, each piece having an inner surface 24 for contacting the foam object 12. The number of pieces that form the mold cavity 18 may depend on the particular shape and/or size of the foam object to be produced and the method used for producing the foam object. As may be appreciated, the mold cavity 18 takes the form of the desired shape of the foam object 12 when the first and second pieces 20, 22 are placed in contact with one another at their extents surrounding the cavity 18.

[0026] As may be appreciated, the foam object 12 is the result of a polymerization reaction performed into the mold 14. For example, during operation of the system 10, various materials are mixed to ultimately produce a foam formulation 30, which is a reactive mixture capable of forming the foam object 12 inside the mold 14 when subjected to suitable polymerization conditions. In the present context, the foam object 12 is a polyurethane foam object. Accordingly, the foam formulation 30 is produced from materials capable of forming repeating carbamate linkages and urea linkages from water and isocyanate. In the illustrated embodiment, the foam formulation 30 is produced by mixing, in a mixing head 32, a polyol formulation 34 and an isocyanate mixture 36. However, it will be appreciated that in certain embodiments, the foam formulation 30 may be produced upon mixing the polyol formulation 34 and the isocyanate mixture 36 directly in the mold cavity 18.

[0027] The polyol formulation 34 may include, among other reactants, polyhydroxyl compounds (e.g., small molecules or polymers having more than one hydroxyl unit including polyols and copolymer polyols) such as polyether polyols. The polyol formulation 34 may also include a blowing agent (e.g., water, volatile organic solvents), a crosslinker, a surfactant, and other additives (e.g., cell openers, stabilizers). The polyol formulation 34 may further include other polymeric materials, such as copolymer materials that are configured to impart certain physical properties to the foam object 12. One example of such a copolymer is a styreneacrylonitirile (SAN) copolymer. Further, in certain embodiments, one or more catalysts configured to facilitate carbamate and urea production may be used, and may be a part of the polyol formulation 34.

[0028] By way of non-limiting example, catalysts may include certain amines (e.g., tertiary amines), amine salts, and/or organometals (e.g., organobismuth and/or organozinc compounds). The catalysts may include a blowing catalyst, a gelling catalyst, or any combination thereof. Commercial examples of catalysts that may be incorporated into the polyol formulation 34 in accordance with present embodiments include DABCO® 331v amine catalyst (l,4-diazabicyclo[2.2.2]octane) available from Sigma Aldrich Co., LLC of St. Louis, MO. and BiCAT® bismuth catalysts available from The Shepherd Chemical Company of Norwood, OH. Table 1 below provides example components of a polyol formulation 34 and their respective amounts.

[0029] The isocyanate mixture 36, which is reacted with the polyol formulation 34 in the mold 14, may include one or more isocyanate compounds. Examples of such compounds include methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), or other such compounds having two or more isocyanate groups. The isocyanate compounds may also include prepolymers or polymers having an average of two or more isocyanate groups per molecule. The particular polyisocyanate compounds used may depend on the desired end use of the foam object 12 (e.g., its desired physical properties).

[0030] As noted, the base material 16 may be a metal or metal alloy and additionally or alternatively may include a polymeric material, ceramics, or any combination thereof. In certain embodiments, the base material 16 may include only polymer materials, or only ceramic materials. By way of example, the ceramic materials may include (e.g., silicon dioxide (Si0₂), titanium dioxide (Ti0₂)), carbides (e.g., silicon carbide), borides, nitrides (e.g., boron nitride), or silicides, or any combination thereof. By way of further example, the polymer materials may include polyethylene (PE), high-density polyethylene (HDPE), low- density polyethylene (LDPE), polypropylene (PP), acrylonitrile butadiene styrene (ABS), polystyrene, polysulfone, nylon, polyvinyl chloride, or similar polymeric material, or a composite of several polymeric materials (e.g., a plastic composite, an epoxy composite, or similar composite) or any thermoplastic capable of providing mechanical stability for the foam produced within the

cavity 18.

[0031] The foam formation reaction may occur either spontaneously due to the presence of a catalyst, or upon the application of heat or another source of energy. The resulting foamed material may then be retained within the mold cavity 18 for a period in which the foam is cured and allowed to harden. For example, the curing process may include heating the foam to between approximately 160 and 180 °F for between approximately 1 and 60 minutes. After curing, in certain embodiments, the foam object 12 may undergo one or more crushing processes (e.g., a time pressure release (TPR) process prior to removal from the mold 14, vacuum 6 crushing after removal from the mold, etc...) in which cell walls are burst to allow gas to escape. [0032] The system 10 includes a release agent 40 that is provided on the inner surface

24 of the mold 14. The release agent composition comprises 5-40 weight % fluorocarbon based polymer in a paste wax basic composition of 60% to 95 weight %. The release agent composition particularly consists essentially of PTFE particles at a concentration of 8-15 weight % in a paste wax basic composition to create a PTFE-wax blend. The 85 - 92 weight % paste wax basic composition and 8-15 weight % PTFE provides a PTFE-wax blend with very good release properties and provides very good physical properties for use in a polyurethane foam object production method discussed below.

[0033] Once the foam object 12 is produced, it may be removed from the mold cavity, or "demolded." The demolded foam object 12 may also undergo one or more finishing steps, such as additional crushing or sanding. It should be noted that during the removal of the foam object 12 from the mold cavity 18, the foam object 12 may be substantially free of surface defects as a result of the superior release properties of a release agent 40 discussed below.

[0034] Over time (e.g., after a certain number of foam production cycles, or once every day, every few days, every week, or every month), it may be desirable to clean the mold cavity 18, for example to remove debris and contaminants, and any foam material. The cleaning may include heating the mold cavity 18 to a temperature that is sufficient to cause softening of foam and/or release agent materials to enable easy removal from the mold 14. Alternatively or additionally, a solvent may be used to remove materials from the mold cavity 18. The release agent 40 may also be re-applied when the mold cavity 18 is cleaned or, alternatively, at different intervals that are independent from the cleaning intervals.

[0035] The fluorocarbon based polymer -wax blend release agent (PTFE-wax blend release agent) 40 of the system 10 is used in the polyurethane foam object production method discussed below. The fluorocarbon based polymer -wax blend release agent 40 may be based on the following examples. [0036] EXAMPLE 1 : 50% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 50% PTFE is prepared as follows:

1. 200g of paste wax (sold under the name ChemTrend PU- 11183 by

Chem-Trend L.P. 1445 W. McPherson Park Drive, Howell, Michigan 48843

U.S.A.) is added to a stainless steel canister.

2. The canister containing the paste wax is heated to 250 °F (121 °C) for 1 hour on a hot plate until the paste wax is liquified.

3. 200g of 1 μπι sized PTFE particles (sold by Sigma Aldrich of 3050 Spruce St., St. Louis, MO 63103) is slowly added to liquified paste wax while mixing with a cow blade mixer at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0037] EXAMPLE 2: 40% PTFE BY WEIGHT IN PASTE WAX: A PTFE-wax blend release agent 40, containing about 40% PTFE is prepared as follows:

1. 200g of paste wax (ChemTrend PU-11183) is added to a stainless steel canister.

3. 133.3g of 1 μηι sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with a cow blade mixer at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0038] EXAMPLE 3: 25% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 25% PTFE, is prepared as follows:

2. The canister containing wax is heated to 250 °F (121 °C) for 1 hour on a hot plate until the paste wax is liquified.

3. 65g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0039] EXAMPLE 4: 15% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 12% PTFE, is prepared as follows:

3. 35.3g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM. 4. The mixture is allowed to continue mixing until the PTFE particles are evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0040] EXAMPLE 5: 12% PTFE BY WEIGHT IN PASTE WAX:

3. 27.3g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0041] EXAMPLE 6: 11% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 11% PTFE, is prepared as follows:

2. The canister containing wax is heated to 250°F (121C°) for 1 hour on a hot plate until the paste wax is liquified.

3. 25g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0042] EXAMPLE 7: 8% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 8% PTFE, is prepared as follows: 1. 200g of paste wax (ChemTrend PU-11183) is added to a stainless steel

canister.

3. 17.4g of 1 μηι sized PTFE particles (Sigma Aldrich) is slowly added to

liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0043] EXAMPLE 8: 5% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 5% PTFE, is prepared as follows:

1. 200g of paste wax (ChemTrend PU-11183) is added to a stainless steel

canister.

2. The canister containing wax (ChemTrend PU-11183) is heated to 250 °F

(121C°) for l hour on a hot plate until the paste wax is liquified.

3. 10.5g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to

liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0044] As for the percent weight content of PTFE, it is determined that useful

PTFE-wax blends could not be formulated with PTFE above 50% due to the paste wax not being pliable enough to spread over surface of a mold tool. The paste wax became hard and chunky. It may be capable of being applied if the tool temperature is above 250 °F. However, a degradation of the paste wax is observed at temperatures of 350 °F.

[0045] The PTFE-wax blend release agents 40 of EXAMPLES 1 - 8 degrade as temperature increases. At 350°F or 180°C, the PTFE-wax blend of EXAMPLE 6 turned yellow in color. Different PTFE-wax blend EXAMPLES can also be prepared with paste waxes that have melting temperatures that are lower and higher than the ChemTrend PU-11183.

[0046] ChemTrend PU 11279 with a minimum melting temperature of 150°F or 80°C can be used for each of the examples noted above instead of the ChemTrend PU-11183. In each case the ChemTrend PU 11279 is heated for lhr at 225 °F (107.2°C) prior to adding PTFE particles. The following are some examples of PTFE-wax blend release agent 40 based on ChemTrend PU 11279.

[0047] EXAMPLE 9: 25% PTFE BY WEIGHT IN PASTE WAX:

1. 200g of paste wax (ChemTrend PU 11279) is added to a stainless steel canister.

2. The canister containing wax is heated to 225 °F (107.2°C) for 1 hour on a hot plate until the paste wax is liquified.

3. 65g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to

liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0048] EXAMPLE 10: 15% PTFE BY WEIGHT IN PASTE WAX:5

1. 200g of paste wax (ChemTrend PU 11279) is added to a stainless steel

canister.

3. 35.3g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature. [0049] EXAMPLE 11: 12% PTFE BY WEIGHT IN PASTE WAX:

3. 27.3g of 1 μηι sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0050] EXAMPLE 12: 11% PTFE BY WEIGHT IN PASTE WAX:

5. The mixture is then allowed to slowly cool to room temperature.

[0051] EXAMPLE 13: 8% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 8% PTFE, is prepared as follows:

2. The canister containing wax is heated to 225 °F (107.2°C) for 1 hour on a hot plate until the paste wax is liquified. 3. 17.4g of 1 μηι sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0052] EXAMPLE 14: 5% PTFE BY WEIGHT IN PASTE WAX:

3. 10.5g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

4. The mixture is allowed to continue mixing until the PTFE particles are

evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0053] ChemTrend PU 14085 with a minimum melting temperature of 230°F or

110°C can be used for each of the examples 1 - 8 noted above instead of the ChemTrend PU-11183. To provide each PTFE-wax blend release agent 40 the ChemTrend PU 14085 is heated for lhr at 305 °F (152°C) prior to adding the PTFE particles. The following are some examples of PTFE-wax blend release agent 40 based on ChemTrend PU 14085.

[0054] EXAMPLE 15: 25% PTFE BY WEIGHT IN PASTE WAX:

1. 200g of paste wax ( ChemTrend PU 14085) is added to a stainless steel canister.

2. The canister containing wax is heated to 305 °F (152°C) for 1 hour on a hot plate until the paste wax is liquified.

3. 65g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to

liquified paste wax while mixing with cow blade at 45 RPM. 4. The mixture is allowed to continue mixing until the PTFE particles are evenly dispersed, the approximate mixing time is 30 minutes.

5. The mixture is then allowed to slowly cool to room temperature.

[0055] EXAMPLE 16: 15% PTFE BY WEIGHT IN PASTE WAX:

1. 200g of paste wax (ChemTrend PU 14085) is added to a stainless steel canister.

5. The mixture is then allowed to slowly cool to room temperature.

[0056] EXAMPLE 17: 12% PTFE BY WEIGHT IN PASTE WAX:

5. The mixture is then allowed to slowly cool to room temperature.

[0057] EXAMPLE 18: 11% PTFE BY WEIGHT IN PASTE WAX:

A PTFE-wax blend release agent 40, containing about 11% PTFE, is prepared as follows: canister.

3. 25g of 1 μηι sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0058] EXAMPLE 19: 8% PTFE BY WEIGHT IN PASTE WAX:

A PTFE -wax blend release agent 40, containing about 8% PTFE, is prepared as follows:

3. 17.4g of 1 μιη sized PTFE particles (Sigma Aldrich) is slowly added to liquified paste wax while mixing with cow blade at 45 RPM.

5. The mixture is then allowed to slowly cool to room temperature.

[0059] EXAMPLE 20: 5% PTFE BY WEIGHT IN PASTE WAX:

5. The mixture is then allowed to slowly cool to room temperature.

[0060] The various examples noted above can be used for polyurethane foam object production as discussed below. It is determined that certain factors can influence release of the polyurethane foam object foam surface from the mold tool.

[0061] It is determined that foam flow is related to the coefficient of friction: with paste wax having a value of 0.18 while PTFE has a value of 0.02-0.04. It is determined that a lower coefficient of friction results in better foam flow. It is determined that a higher PTFE loading (a higher percentage of PTFE to paste wax in the PTFE-wax blend release agent 40) results in better foam flow.

[0062] Larger PTFE particles (greater than 1 micron) will result in more of the Teflon being exposed to the foam chemistry leading to consistent release over a longer period of time, however, this exposure will result in the foam mechanically bonding with the particles and leading to loss of the particles over time and corresponding release properties. [0063] Smaller PTFE particles (1 micron or less) will minimize this effect leading to a coating that maintains release properties over time, however, the resulting paste wax blend will have a higher coefficient of friction (greater than the coefficient of Teflon, 0.02) leading to slower foam flow than what would be observed for a pure teflon coating. The PTFE in paste wax blend should still exhibit better foam flow than paste wax alone which has a coefficient of friction of 0.18.

[0064] Depending a release properties required, PTFE particle size can be selected to achieve the desire properties needed for the specific foam process being used.

[0065] As shown in Figure 2, several examples were tested based on different PTFE weight % (TEFLON loading) and different wax melt points based on: (1) ChemTrend PU 11183 (medium temperature MT); (2) ChemTrend PU 11279 (low temperature LT); and (3)

ChemTrend PU 14085 (high temperature HT). The examples tested included three examples with 5 weight % PTFE and 95 weight % paste wax, which examples had different wax melt points based on (1) ChemTrend PU 11183, (2) ChemTrend PU 11279 or (3) ChemTrend PU 14085. The examples tested included three examples with 15 weight % PTFE and 85 weight % paste wax, which examples had different wax melt points based on (1) ChemTrend PU 11183, (2) ChemTrend PU 11279 or (3) ChemTrend PU 14085. The examples tested included three examples with 20 weight % PTFE and 80 weight % paste wax, which examples had different wax melt points based on (1) ChemTrend PU 11183, (2) ChemTrend PU 11279 or (3) ChemTrend PU 14085.

[0066] As discussed above, the isocyanate mixture 36, which is reacted with the polyol formulation 34 in the mold 14, may include one or more isocyanate compounds. As indicated in Figure 2, the examples tested were based on TDI (toluene diisocyanate - isomers 2,4' and 2,6' commonly used for molded polyurethane foams), MDI (methylene diphenyl diisocyanate - isomers 2-2', 2,4' and 4,4' commonly used for molded polyurethane foams). Other blends are also available in the market, such as TM20 (a blend of TDI and MDI where the 20 indicates the content level of MDI), TM10, TM80, etc but they are not as common for molded polyurethane foams. The polyol formulation is listed under the column heading

"Formulation" and may be as noted above or as described in US patent application publication 2010/0291369 Al (see in particular paragraph 0047), which US patent application publication 2010/0291369 Al is incorporated by reference in its entirety. The column "noise" relates to the nature of the surface of the mold part (such as "N = new" and "SB = Blasted") and the column "Poured Where" relates to the particular system set up used.

[0067] The number of polyurethane foam objects released, before the need to repeat the application of the PTFE -wax blend release agent 40 is noted (Releases Achieved). The number of releases is very high, including 76 releases achieved for 15 weight % PTFE and 85 weight % paste wax. [0068] For each of the EXAMPLES 1 - 20 of PTFE-wax blend release agent 40, a non-reactive pigment may be added in the mixing stage 4. This produces a PTFE-wax blend release agent with pigment. This is useful to assist with visually monitoring the loss of coating with each release.

[0069] For each of the EXAMPLES 1 - 20 of PTFE-wax blend release agent 40, a reactive pigment can be added to the coating in the mixing stage 4, to actually allow the surface of the foam to be colored without having to add pigment to foam formulation. This produces a PTFE-wax blend release agent with a reactive pigment.

[0070] The above present examples only. Other fluorocarbon based polymer -wax blend release agents including other PTFE in paste wax compositions may still provide the advantages according to the invention. It has been noted that compositions with a high percentage of PTFE, such as more than 40%, result in a composition that is too dry and which crumbles. Accordingly the preferred maximum PTFE loading level is 40%. Other PTFE-wax blend release agent compositions, with preferably 5-40% PTFE and 95% - 60% paste wax basic composition may also be provided according to the invention. PTFE-wax blend release agent compositions, with 8-15% PTFE and 85% - 92% paste wax basic composition are particularly preferred.

POLYURETHANE FOAM OBJECT PRODUCTION METHOD:

[0071] A polyurethane foam object production method for producing a polyurethane molded part is provided using the system 10 described above. The system 10 includes a fluorocarbon based polymer -wax blend release agent 40, such as any one of the PTFE in paste wax compositions discussed above (EXAMPLES 1 - 20) to form the layer of fluorocarbon based polymer -wax blend release agent (particularly PTFE-wax blend release agent) 40.

[0072] The method includes a basic aluminum molding tool preparation procedure is as follows. The temperatures suggested within this procedure are based on a paste wax with a minimum melting temperature of 175 °F, these temperatures are adjusted accordingly based on the melting temperature of the base paste wax being utilized

1. Any existing debris from the mold tool is removed (clean mold).

2. The tool is heated to 250°F (e.g., placed oven - or equivalent - at 250°F).

3. One of the PTFE in paste wax compositions is wiped onto the entire surface while still warm.

4. The tool is heated at 250 °F for 1 hr (e.g., placed oven - or equivalent - at

250 °F) to melt paste wax and to seal off pores, of the surfaces, in the tool. 5. Heating is stopped (e.g., the tool is removed from the oven) and excess

PTFE containing paste wax is wiped off.

6. The substrate/tool is then either left at 170°F or cooled down to room

temperature prior to pouring foam parts.

[0073] The mold tools 20, 22 are then heated to 250 °F. The fiuorocarbon based polymer -wax blend release composition (such as the PTFE in paste wax composition) according to the invention is applied by rubbing the fiuorocarbon based polymer -wax (PTFE in paste wax) composition on the multiple surfaces 24 of the wall 14 using a cloth, brush, or rag. Foam Scraps should not be used for application. The molding tools 20 and 22 are heated to a temperature of 250 °F so as to allow the PTFE in paste wax composition to melt and soak into surface pores and fill surface pores of the mold tools 20, 22 of the mold 14. The PTFE in paste wax composition is applied to achieve a visibly even coating of the surface. Rigid seat components may be fed in as shown at 38. This provides a layer of PTFE in paste wax composition 40, that forms a barrier between the foam formulation material 30 and/or rigid seat components 28 and the mold tools 20, 22 of the mold 14. All of the surfaces of the mold 14, that are to come in a contact with the mold material, are preferably coated. However, particular regions of the mold 14 may be left uncoated, as discussed further below. The mold tools 20 and 22 are then allowed to cool. The combination of features provides a system 10 that has a PTFE in paste wax composition layer 40.

[0074] Polyurethane foam object production then commences using the system 10.

Individual mold products are produced and released (indicated by 26) from the mold 14. Based on the provision of the a PTFE in paste wax composition layer 40 as discussed above, foam products 18 may be produced and released with between 2 to 80 process cycles between spray mold release applications, for each process cycle, namely for each application of the PTFE in paste wax composition layer 40 according to the invention.

[0075] According to a variant of the foam object production, regions of the mold 14 may be left uncoated with the PTFE in paste wax composition according to the invention. This provides a PTFE in paste wax composition 40 on the surface 24 with an adjacent uncoated area on the surface 24 or an uncoated area on another surface 24. This is particularly useful with at least one of the mold tools 20, 22, of the overall mold 14, being provided as a component of the eventual product that includes the form object 12. After formation of the form object 12, the form object 12 is attached to or includes what had previously formed a part of the mold 14. For example, the mold 14 includes a mold tool part 42 which together with other mold tool parts (mold pieces 20 and 22), completes the molding cavity 18. In this case the PTFE in paste wax composition according to the invention 40 is not applied to the surface of the mold tool part 42. The foam product 12 is then removed from the mold cavity along with the attached mold tool part 42, which is now connected with the foam object 12 and forms a part of the mold product 12.

[0076] While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

Claims

WHAT IS CLAIMED IS:

1. A fluoropolymer-wax blend release agent composition consisting essentially of 8 - 15 weight % fluoropolymer and 85 - 92 weight % paste wax basic composition.

2. A fluoropolymer-wax blend release agent composition according to claim 1, wherein the fluoropolymer is polytetrafluoroethylene (PTFE) and the paste wax basic composition comprises 58-72 weight % hydrocarbon naphtha and 28-42 weight % release blend.

3. A fluoropolymer-wax blend release agent composition according to any of claims 1 and 2, wherein the fluoropolymer is polytetrafluoroethylene (PTFE) in particle form with a particle size of 1 micron or less.

4. A fluoropolymer-wax blend release agent composition according to any of claims 1, 2 and 3, in combination with a reactive pigment or a non-reactive pigment.

5. A fluorocarbon based polymer- wax blend release agent composition comprising 5 - 50 weight % fluorocarbon based polymer and 50 - 95 weight % paste wax and preferably comprising 5 - 40 weight % fluorocarbon based polymer and 60 - 95 weight % paste wax and more preferably comprising 8 - 15 weight % fluorocarbon based polymer and 85 - 92 weight % paste wax.

6. A release agent composition according to claim 5, wherein the fluorocarbon based polymer is polytetrafluoroethylene (PTFE).

7. A release agent composition according to any of claims 5 and 6, wherein the paste wax is a paste wax basic composition comprising 58-72 weight % hydrocarbon naphtha and 28-42 weight % release blend.

8. A release agent composition according to any of claims 5, 6 and 7, wherein the fluoropolymer is polytetrafluoroethylene (PTFE) in particle form with a particle size of 1 micron or less.

9. A release agent composition to any of claims 5, 6, 7 and 8, in combination with a reactive pigment or a non-reactive pigment.

10. A polyurethane foam object production system comprising:

a mold comprising at least one mold tool; and

a layer of a fiuorocarbon based polymer- wax blend release agent composition according to any of claims 1 - 9.

11. A polyurethane foam object production method comprising the steps of:

providing a polyurethane foam object production system according to claim 10;

cleaning the mold tool;

heating the mold tool;

applying the fiuorocarbon based polymer-wax blend release agent composition to a surface of the heated mold tool to melt the fiuorocarbon based polymer- wax blend release agent such that the fiuorocarbon based polymer- wax blend release agent fills surface pores of the mold tool;

cooling the mold tool to provide the mold tool with a fiuorocarbon based polymer- wax blend release agent surface layer; and

producing a plurality of individual mold products and releasing the plurality of individual mold products from the mold with the mold tool with the fiuorocarbon based polymer- wax blend release agent surface layer.