SYSTEMS, DEVICES AND METHODS FOR DISPENSING AND CURING SILICONE BASED TOPICAL SKIN ADHESIVES
20210369258 · 2021-12-02
Inventors
- Duan Li Ou (Watchung, NJ, US)
- Frank Richard Cichocki, Jr. (Easton, PA, US)
- Glenn R. Cook (Clinton, NJ, US)
Cpc classification
A61M5/19
HUMAN NECESSITIES
A61B2017/005
HUMAN NECESSITIES
B05C17/00516
PERFORMING OPERATIONS; TRANSPORTING
B05C17/00553
PERFORMING OPERATIONS; TRANSPORTING
International classification
Abstract
A system for dispensing a curable composition includes a dual barrel syringe including a first syringe barrel with a first plunger, and a second syringe barrel with a second plunger. A static mixer is connected with distal ends of the first and second syringe barrels. The first and second plungers are moveable toward the distal ends of the first and second syringe barrels for expelling first and second components of a curable composition from the distal ends of the barrels into the static mixer for mixing the components to form the curable composition. A flexible spreader connected with a distal end of the static mixer has a flat dispensing opening, and a plurality of channels extending to the flat dispensing opening to dispense the curable composition. A hot gas blower generates a hot gas stream flowing distally over the distal end of the flexible spreader for curing the curable composition.
Claims
1. A system for dispensing a curable composition comprising: a delivery device; a static mixer having a proximal end that is connected with a distal end of said delivery device; a flexible spreader having a proximal end that is connected with a distal end of said static mixer, a distal end including a flat dispensing opening, and a plurality of channels extending through said flexible spreader to said flat dispensing opening.
2. The system as claimed in claim 1, further comprising a hot gas blower configured to generate a hot gas stream that flows distally over the distal end of said flexible spreader.
3. The system as claimed in claim 1, wherein said delivery device contains at least one component of a curable composition, and wherein said delivery device is configured to expel said at least one component from said delivery device into the proximal end of said static mixer.
4. The system as claimed in claim 3, wherein said delivery device includes a dual barrel syringe comprising: a first syringe barrel containing a first component of said curable composition and a first plunger disposed within said first syringe barrel; a second syringe barrel containing a second component of said curable composition and a second plunger disposed within said second syringe barrel, wherein said first and second plungers are moveable toward distal ends of said respective first and second syringe barrels for expelling said first and second components from the distal ends of said respective first and second syringe barrels and into the proximal end of said static mixer.
5. The system as claimed in claim 4, further comprising a tab interconnecting proximal ends of said first and second plungers for simultaneously moving said first and second plungers toward the distal ends of said respective first and second syringe barrels for expelling said first and second components.
6. The system as claimed in claim 1, wherein said static mixer comprises: a static mixing tube having a proximal end with a proximal opening, a distal end with a distal opening, and a conduit that extends from the proximal opening to the distal opening; at least one helical baffle disposed within the conduit of said static mixing tube, wherein said at least one helical baffle includes helically wounds blades adapted to mix said first and second components together to form said curable composition as said first and second components flow from the proximal end to the distal end of said static mixing tube.
7. The system as claimed in claim 1, wherein said flexible spreader includes a flexible blade having a proximal end and a distal end, said flexible blade comprising: a first wall extending from the proximal end to the distal end of said flexible blade; a second wall extending from the proximal end to the distal end of said flexible blade; said plurality of channels extending between said first and second walls to said flat dispensing opening at the distal end of said flexible spreader.
8. The system as claimed in claim 7, wherein said flexible blade is made of a material selected from the group consisting of silicones, rubbers, and polymers having a 0-80 durometer Shore A hardness rating.
9. The system as claimed in claim 7, wherein said flexible spreader further comprises a plurality of spaced posts extending from said first wall to said second wall for defining said plurality of channels.
10. The system as claimed in claim 9, wherein said first wall has an inner surface and said second wall has an inner surface that opposes said inner surface of said first wall, wherein said spaced posts extend from said inner surface of said first wall to said inner surface of said second wall.
11. The system as claimed in claim 7, wherein the distance between the proximal ends of said first and second walls of said flexible blade is greater than the distance between the distal ends of said first and second walls of said flexible blade.
12. The system as claimed in claim 7, wherein said flexible blade has a first width at the proximal end thereof and a second width at the distal end thereof that is greater than the first width so that the distal end of said flexible blade is wider than the proximal end of said flexible blade.
13. The system as claimed in claim 3, wherein said curable composition is selected from the group consisting of polyurethane, acrylic, methyl methacrylate, silicone, condensation cured silicone, epoxy, polysulfide, and high viscosity curable biocompatible compositions having viscosities greater than 5000 cps.
14. The system as claimed in claim 3, wherein said curable composition comprises: a cross-linkable silicone polymer having reactive functionalities; a silica-containing composition; a silicone cross-linking agent; and, a catalyst, wherein said catalyst comprises a platinum tetramethyldivinyl disiloxane diethyl maleate complex having the formula:
Pt[(CH.sub.2═CH)(CH.sub.3).sub.2Si].sub.2O.(COOH═CHCO)(C.sub.2H.sub.5O).sub.2.
15. The system as claimed in claim 14, wherein the cross-linkable silicone polymer is selected from the group consisting of vinyl terminated polydialkylsiloxane, vinyl terminated polydimethylsiloxane, vinyl terminated polydiphenylsilane-dimethylsiloxane copolymer, vinyl terminated polyphenylmethylsiloxane, vinyl terminated polyfluoropropylmethyl-dimethylsiloxane copolymer, vinyl terminated polydiethylsiloxane, and SiH terminated polydimethyldisiloxane.
16. A system for dispensing a curable composition comprising: a dual barrel syringe including a first syringe barrel containing a first component of a curable composition and a first plunger disposed within said first syringe barrel, a second syringe barrel containing a second component of said curable composition and a second plunger disposed within said second syringe barrel; a static mixer having a proximal end that is connected with distal ends of said respective first and second syringe barrels, wherein said first and second plungers are moveable toward the distal ends of said respective first and second syringe barrels for expelling said first and second components from the distal ends of said respective first and second syringe barrels into the proximal end of said static mixer for mixing said first and second components to form said curable composition; a flexible spreader having a proximal end that is connected with a distal end of said static mixer, a distal end including a flat dispensing opening, and a plurality of channels extending to said flat dispensing opening that are configured to deliver said curable composition from said static mixer to said flat dispensing opening; a hot gas blower configured to generate a hot gas stream that flows distally over the distal end of said flexible spreader for curing said curable composition dispensed from said flat dispensing opening.
17. The system as claimed in claim 16, wherein said flexible spreader includes a flexible blade having a proximal end and a distal end, said flexible blade comprising: a first wall extending from the proximal end to the distal end of said flexible blade; a second wall extending from the proximal end to the distal end of said flexible blade; a plurality of spaced posts extending from said first wall to said second wall for defining said plurality of channels extending between said first and second walls to said flat dispensing opening at the distal end of said flexible spreader.
18. The system as claimed in claim 17, wherein said spaced posts are arrayed in a matrix pattern, and wherein said plurality of channels extend between said spaced posts to define tortuous flow paths for said curable composition flowing through said flexible blade to said flat dispensing opening.
19. The system as claimed in claim 16, wherein said flexible spreader is made of a material selected from the group consisting of silicones, rubbers, and polymers having a 0-80 durometer Shore A hardness rating.
20. The system as claimed in claim 17, wherein the distance between the proximal ends of said first and second walls of said flexible blade is greater than the distance between the distal ends of said first and second walls of said flexible blade, and wherein said flexible blade has a first width at the proximal end thereof and a second width at the distal end thereof that is greater than the first width so that the distal end of said flexible blade is wider than the proximal end of said flexible blade.
21. A method of dispensing a curable composition comprising: simultaneously expelling two components from a delivery device into a static mixer; mixing said two components together within said static mixer to form a curable composition; directing said curable composition into a flexible spreader having a plurality of channels that extend to a flat dispensing opening located at a distal end of said flexible spreader; dispensing said curable composition from said flat dispensing opening onto a surface; using one or more outer surfaces of said flexible spreader for spreading said dispensed curable composition onto the surface.
22. The method as claimed in claim 21, further comprising directing a stream of hot gas onto said curable composition for curing said curable composition.
23. The method as claimed in claim 21, wherein said flexible spreader includes a flexible blade having a proximal end and a distal end, said flexible blade comprising: a first wall extending from the proximal end to the distal end of said flexible blade; a second wall extending from the proximal end to the distal end of said flexible blade; a plurality of spaced posts extending from said first wall to said second wall for defining said plurality of channels having tortuous flow paths extending between said first and second walls to said flat dispensing opening at the distal end of said flexible spreader.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0084] Referring to
[0085] In one embodiment, the system 100 for dispensing the curable composition may include a static mixer 114 that is located downstream from the distal ends of the respective first and second barrels 104, 108. In one embodiment, a connector 116 preferably couples the distal ends of the respective first and second barrels 104, 108 with the proximal end of the static mixer 114. In one embodiment, the first and second components that are expelled from the distal ends of the first and second barrels 104, 108 are desirably mixed together within the static mixer 114 for forming the curable composition.
[0086] In one embodiment, the system 100 for dispensing the curable composition preferably includes a flexible spreader 118, such as a component having the shape of a spatula, a spackle spreader and/or a putty knife, which is desirably connected to a distal end of the static mixer for dispensing the curable composition that is mixed within the static mixer 114. In one embodiment, the flexible spreader 118 may have a flexible blade 120 with an elongated, flat dispensing opening located at a distal end thereof for dispensing the curable composition onto a surface (e.g., a skin surface, tissue, a wound). The one embodiment, the curable composition may be dispensed as a ribbon of curable composition having a length and a width. In one embodiment, the mixture of the first and second components that is expelled from a distal end of the static mixture is forced through the flexible blade 120 of the flexible spreader 118 for being dispensed from an elongated, flat dispensing opening located at the distal end of the flexible blade. The flexible blade 120 may be used for spreading the dispensed curable composition over a surface, such as a skin surface or a surgical mesh applied over tissue. In one embodiment, the flexible spreader and/or the flexible blade may be made of silicone, rubber, or a polymer material.
[0087] In one embodiment, the system 100 for dispensing a curable composition preferably includes a hot gas blower 122 that desirably generates a stream of hot gas 124 (e.g., ambient air; an inert gas) that is directed in the distal direction DIR1 for curing the curable composition that is dispensed from the distal end of the flexible blade 120 of the flexible spreader 118. In one embodiment, the hot gas blower 122 preferably includes an actuator 126 (e.g., a button) that may be in engaged to actuate the hot gas blower for generating a hot gas stream 124 that is dispensed in the distal direction DIR1 toward the distal end of the flexible blade 120 of the flexible spreader 118. In one embodiment, the hot gas blower 122 may be powered by an electrical power cord or a power source (e.g., a battery).
[0088] In one embodiment, the system 100 for dispensing a curable composition preferably includes a temperature sensor 128 that desirably monitors the temperature level of the hot gas 124 that is dispensed from the hot gas blower 122. The temperature sensor 128 may be located on the hot gas blower 122. Monitoring and controlling the temperature level of the hot gas that is discharged by the hot gas blower preferably insures that the temperature level of the hot gas 124 is maintained within a safe range for not damaging the patient's tissue and/or is maintained within a preferred temperature range for efficiently and effectively curing the curable composition.
[0089] Referring to
[0090] Referring to
[0091] In one embodiment, the proximal end 134 of the static mixing tube 128 preferably includes a connecting structure 144 formed on the outer surface of the tubular-shaped wall 132 for connecting the proximal end 134 of the static mixing tube 128 with the connector 116 located at the distal ends of the respective first and second syringe barrels 104, 108 (
[0092] Referring to
[0093] Referring to
[0094] Referring to
[0095] Referring to
[0096] Referring to
[0097] Referring to
[0098] Referring to
[0099] In one embodiment, the first wall 158 of the flexible blade 120 preferably has a first major surface 162 and the second wall 160 of the flexible blade 120 preferably has a second major surface 163, whereby the first and second major surfaces 162, 163 are outer surfaces of the flexible blade that may be used for spreading the curable composition after it has been dispensed from the elongated, flat dispensing opening 156.
[0100] In one embodiment, the flexible spreader 118 preferably includes a plurality of spaced posts 164 that extend from an inner surface of the first wall 158 to an opposing, inner surface of the second wall 160. The posts 164 preferably span the space that is present between the first wall 158 and the second wall 160 to form a plurality of flow channels for the curable composition that have tortuous pathways between the proximal and distal ends of the flexible spreader 118. The flow channels preferably define the tortuous pathways for the flowing curable composition, which are adapted to breakup and/or eliminate any air or gas bubbles that are present in the curable composition before it is dispensed from the elongated, flat dispensing opening 156 of the flexible spreader 118.
[0101] Referring to
[0102] Referring to
[0103] In one embodiment, the first and second walls 158, 160 of the flexible blade 120 preferably taper inwardly toward one another from the proximal end 150 of the flexible spreader 118 to the distal end 154 of the flexible spreader 118. As a result, the spacing S.sub.1 between proximal ends of the first and second walls 158, 160 is greater than the spacing S.sub.2 between distal ends of the first and second walls 158, 160. In one embodiment, the gap or spacing S.sub.2 of the flat dispensing opening is desirably about 0.5-3.0 mm.
[0104] In one embodiment, the flexible spreader 118 preferably includes a plurality of spaced posts 164 that extend from the first wall 158 to the second wall 160 of the flexible blade 120 to form the plurality of narrow channels 174 that extend between the posts 164 for breaking up any air or gas bubbles that are present in the curable composition as the curable composition flows distally in the direction DIR1 from the proximal end 150 to the distal end 154 of the flexible spreader 118.
[0105] Referring to
[0106] In one embodiment, the spaced posts 164 may be divided into rows of posts 164A-164F, whereby the posts in any one row have heights that are greater (i.e., taller) in the center of the flexible blade 120 and smaller (i.e., shorter) in the lateral regions of the flexible blade 120. In one embodiment, the posts 164 within any one row may become progressively shorter when moving from a central region of the row to outer, lateral regions of the row.
[0107] Referring to
[0108] Referring to
[0109] Referring to
[0110] In one embodiment., the distal end of the flexible blade 220 preferably includes an elongated, flat dispensing opening 256 that extends across the width of the flexible blade 220 at the distal end of the flexible blade, In one embodiment, after the first and second components of a high viscosity curable composition have been mixed together within the static mixing tube of the static mixer 114 shown and described above in
[0111] Referring to
[0112] Referring to
[0113] In one embodiment, the first wall 258 of the flexible blade 220 preferably has a first major surface 262 (e.g., an outer surface) and the second wall 260 of the flexible blade 220 preferably has a second major surface 263 (e.g., an outer surface), whereby the first and second major surfaces 262, 263 may be used for spreading the curable composition that is dispensed from the elongated, flat dispensing opening 256.
[0114] In one embodiment, the flexible spreader 218 includes a plurality of the spaced posts 264 that extend from an inner surface of the first wall 258 to an opposing, inner surface of the second wall 260. The posts 264 preferably span the space or gap that is present between the first wall 258 and the second wall 260 to form a plurality of different, distinct flow channels 274 between the proximal and distal ends of the flexible spreader 218. The flow channels preferably define a plurality of tortuous pathways for the curable composition as it flows through the flexible spreader, which are adapted to breakup and/or eliminate any air or gas bubbles that are present in the curable composition before the curable composition is dispensed from the elongated, flat dispensing opening 256, which is located at the distal end 254 of the flexible blade 220 of the flexible spreader 218.
[0115] Referring to
[0116] Referring to
[0117] In one embodiment, the first and second walls 258, 260 of the flexible blade 220 preferably taper inwardly toward one another from the proximal end 250 of the flexible spreader 218 to the distal end 254 of the flexible spreader 218. As a result, the flexible blade may be thicker at a proximal end thereof and thinner at a distal end thereof, whereby the spacing S.sub.3 between proximal ends of the first and second walls 258, 260 (i.e., at the proximal end of the flexible blade 220) is greater than the spacing S.sub.4 between distal ends of the first and second walls 258, 260 (i.e., at the distal end of the flexible blade 220).
[0118] Referring to
[0119] Referring to
[0120] In one embodiment, the spaced posts 264 may be divided into rows of posts 264A-264F, whereby the posts in any one row have heights that are greater (i.e., taller) in the center of the flexible blade 220 and smaller (i.e., shorter) in the lateral regions of the flexible blade 220. In one embodiment, the posts 264 within a row may become progressively shorter when moving from a central region of the row to the outer, lateral regions of the row.
[0121] In one embodiment, one of the parts of the two part silicone based topical skin adhesive may include a catalyst for precipitating a chemical reaction between the two parts of the silicone adhesive.
[0122] Karstedt of GE Silicone invented a highly active platinum catalyst at the beginning of the 1970's, which was disclosed in U.S. Pat. No. 3,775,452. Vinyl terminated polydimethylsiloxane can react with polymethylhydrosiloxane containing cross linker in less than 1 minute at ambient temperature with as little as 10 ppm of the Karstedt catalyst. The traditional platinum catalyst does not enable the reaction between OH groups on the surface of silica particles reacts and the OH functions on the surface of substrate. This type of condensation reaction tends to be slow at ambient condition and the typical catalyst for this reaction including organic amine and catalyst such as tin dilaurate. Trace amount of condensation catalyst will terminate the catalytic ability of platinum catalyst which is referred as platinum poisoning in the silicone industry. A novel platinum comparable catalyst is needed to activate the OH condensation between silica particle and substrate material, to enable rapid adhesion formation between silicone and a given substrate material. A platinum based novel catalyst of the present invention is able to activate both vinyl silylation and OH condensation simultaneously.
[0123] The novel catalyst disclosed in the present patent application is prepared by reacting Karstedt's catalyst with diethyl maleate according to Scheme 1. The novel platinum tetramethyldivinyl disiloxane diethyl maleate catalyst enables both vinyl silylation and a condensation reaction. This is referred to as a “dual functional silicone catalyst”.
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[0124] The novel catalyst disclosed in the present patent application may be prepared in the following manner: a Karstedt catalyst in xylene solution is mixed with diethyl maleate at ambient temperature for a sufficiently effective time to complete the reaction, e.g., 10 hours.
[0125] The resulting catalyst solution containing the novel catalyst of the present patent application is ready to use in a composition useful as a topical skin adhesive. The formula of the resulting platinum complex catalyst (platinum tetramethyldivinyl disiloxane diethyl maleate complex) is:
Pt[(CH.sub.2═CH)(CH.sub.3).sub.2Si].sub.2O.(COOH═CHCO)(C.sub.2H.sub.5O).sub.2.
[0126] It should be noted that the resulting catalyst reaction mixture will contain a small amount of the reaction product divinyltetramethyldisiloxane. This component does not affect the catalyst and is a low boiling point component that is rapidly evaporated. Accordingly, purification of the catalyst mixture to remove divinyltetramethyldisiloxane is optional, and it is believed that its presence at ultra low concentrations will not affect the cross-linking reaction of a cross-linkable silicone polymer. The novel catalyst of the present invention also actives the bonding formation between silanol groups on the surface of silica fillers and OH functions on a given surface, that is, the catalyst is capable to activate two reactions. This allows for curing the cross-linkable components in silicone coatings to rapidly form coating films at desired curing temperatures and provides bonding to a given substrate such as human skin.
[0127] In one embodiment, a curable composition may include a catalyst, which may be formulated as set forth in Example 1 of the present patent application.
EXAMPLE 1
Novel Platinum Catalyst (Synthesis Procedure)
[0128] 44.50 g of Gelest SIP 6831.2 (2.2% platinum divinyl tetramethyldisiloxane complex in xylene, Karstedt catalyst) was mixed with 2 g of diethyl maleate for 24 hours at ambient temperature. Samples were taken out after 3 hours, 18 hours, and 24 hours for NMR testing and the NMR spectra for the 3 hour sample is shown in
[0129] The formation of the novel catalyst is the evidence for scheme 1, which rests on NMR spectroscopic identification. Karstedt catalyst is known with a characteristic .sup.195Pt signal at approximately −6111 ppm.
[0130] After 3 hours of mixing of the mixtures of Example 1, a new .sup.195Pt signal at −6082 ppm was observed along with the original signal for the Karstedt catalyst at −6111 ppm as illustrated in the NMR spectra of this mixture at 3 hours in
[0131] In one embodiment, the curable composition may include silicone-based topical skin adhesives, which are formulated as set forth below in Examples 2 and 3 of the present patent application.
EXAMPLE 2
Preparation of Silicone-Based Topical Skin Adhesive
[0132] In general and similar to most of commercially available platinum cured silicone materials, the silicone-based topical skin adhesive is delivered in a two-part kit by mixing equal volumes of the Part A and Part B components.
[0133] As an overview, vinyl terminated polydimethylsiloxane is mixed with Platinum tetramethyldivinyl disiloxane diethyl maleate catalyst, silica particles and optionally aliphatic organic solvent using a high-speed mixer to form part A of the kit. Vinyl terminated polydimethylsiloxane were mixed with polymethylhydro-co-polydimethylsiloxane cross linker, silica particle and optionally aliphatic organic solvent using high speed mixer to form part B of the kit.
[0134] Equal amounts of the two-part kit were mixed using a static mixer and then spread onto the surface of a substrate, such as skin. The mixture of the two-part kit cured within 5 minutes at body temperature as determined by the loss of stickiness or tackiness of the applied silicone.
[0135] Part A. 40 g of vinyl terminated polydimethylsiloxane (Gelest DMSV41) was mixed with 10 g of surface treated silica particles (Gelest SIS6962.0), together with 2.6 g of the resulting catalyst of Examplel using a high-speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
[0136] Part B. 40 g of vinyl terminated polydimethylsiloxane (Gelest DMSV41) was mixed with 10 g of surface treated silica particles (Gelest SIS6962.0), together with 3.34 g of Polymethylhydro-co-polydimethylsiloxane (Gelest HMS301) using a high-speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
EXAMPLE 3
Preparation of Silicone-Based Topical Skin Adhesive Using Commercial Silica-Containing Silicone Raw Material
[0137] Part A. 90 g of Elkem 44 experimental base (containing vinyl terminated polydimethyl silicone base polymer and fume silica particles) was mixed with 4.72 g of the resulting catalyst of Example 1, 9.0 g of low molecular weight vinyl terminated polydimethyl silicone base polymer (Gelest DMS V21) and 26 g of hexane using a high-speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
[0138] Part B. 81 g of Elkem 44 experimental base (containing vinyl terminated polydimethyl silicone base polymer and fume silica particles) was mixed with 8.1 g of polymethyl hydro siloxane cross linker (Gelest DMS H991), 2.7 g of SiH terminated polydimethylsiloxane chain extender (Gelest DMS H21) and 10.2 g of hexane using a high speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
[0139] Control Example: Control Example Without Silica Bonding Agent and Using Conventional Karstedt Catalyst
[0140] Part A. 40 g of vinyl terminated polydimethylsiloxane (Gelest DMSV41) was mixed with 2.6 g of Karstedt catalyst xylene solution (1% of Gelest SIP 6831.2 in xylene) using a high-speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
[0141] Part B. 40 g of vinyl terminated polydimethylsiloxane (Gelest DMSV41) was mixed 3.34 g of Polymethylhydro-co-polydimethylsiloxane (Gelest HMS301) using a high-speed centrifugal mixer (FlackTek DAC150 FV-K) at 3470 rpm for 5 minutes.
[0142] As noted above and as would be appreciated by one of skill in the art, the silicone compositions disclosed in the present patent application cure in several minutes to films that are neither sticky nor tacky. In contrast, some silicone adhesives, such as silicone pressure sensitive adhesives (PSA's), are by nature sticky or tacky and are intended to be such for the entire usable life of the adhesive. Such useable life of the tacky silicone PSA's may be upwards to several years. The non-tackiness of the compositions and examples of this invention is measured by ASTM 0679.
[0143] In general ASTM C679 consists of lightly touching a surface of a curing sealant with a polyethylene film at regular intervals until the sealant does not attach itself to the film and the film appears clean when peel from the surface. More specifically a strip of polyethylene film is placed on the surface of the curing elastomer and a 30 g weight is placed on the film. The weight is left in place for 30 seconds, then removed and the polyethylene strip is removed and examined for sealant attachment to the film. The length of time from when the sealant was first applied onto a given surface until the time the sealant is no longer picked up by the film is called tack-free time and is the time point at which the film exhibits a non-tacky nature which evidences that the sealant has cured.
[0144] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, which is only limited by the scope of the claims that follow. For example, the present invention contemplates that any of the features shown in any of the embodiments described herein, or incorporated by reference herein, may be incorporated with any of the features shown in any of the other embodiments described herein, or incorporated by reference herein, and still fall within the scope of the present invention.