Compositions and methods for providing a release coating

Abstract

Aqueous compositions that can be used to impart release properties to adhesive tape substrates can be applied at coat weights that are much lower than those required for previously available compositions containing the same or similar release polymers. The inclusion of small amounts of superwetters results in improved coatability and a reduction in the amount of sound emitted during the process of peeling the adhesive tape from its roll.

Description

[Technical Field]

[0001] Background technical information Adhesive tapes, generally supplied in roll form, are advanced technical articles comprising, as their main components, a substrate and adhesive and low-adhesion backsize (LAB) provided on opposite main surfaces of the substrate, respectively. The low-adhesion backsize (LAB) provides reversible bonding or the ability to unwind the roll product, despite the fact that the adhesive layer supported on one layer of the substrate is adjacent to another layer of the substrate, thereby improving handling characteristics. For further details regarding the composition and general physical form of LAB, interested readers should refer to Chapter 26 of D. Satas, “Release Coatings”, Handbook of Pressure Sensitive Adhesive Technology, 3rd ed. (1999).

[0002] The main types of substrates used in the manufacture of adhesive tapes are fibrous materials (e.g., paper) and polymer films. Each of these presents its own set of challenges in terms of providing a good laboratory-based application (LAB).

[0003] In the case of polymer film backings, the provision of LAB relates to so-called release agents. Examples of release agents include nonionic surfactants, long-chain alkyl carboxylic acids and esters, (meth)acrylates having long-chain side groups, polyurethanes, silicone polymers (especially polydialkylsiloxane homo and copolymers), and fluorinated polymers and waxes. For further details on release agents, interested readers should refer to one of the various texts and overviews, such as Chapter 12 of Kenning and Schneider, “Release Coatings for Pressure Sensitive Adhesives”, Adhesion Science and Engineering - Surfaces, Chemistry, and Applications, pp. 535-71 (2002). Coating technologies include: (1) a technique for obtaining a release film of release agents (one or more) incorporated into a polymer network by applying a liquid composition (e.g., emulsion, suspension, dispersion) containing a film-forming polymer and one or more release agents, followed by drying; and (2) extrusion molding of a LAB composition containing one or more release agents blended with an extrudeable polymer such as polyolefin.

[0004] Silicone compounds (i.e., polysiloxanes) can be very effective release agents, either alone or blended with hydrocarbon polymers. However, small amounts of silicone compounds can often migrate into adhesives, causing "craters" or "fish eyes."

[0005] Certain adhesive articles provide release properties using non-silicone polymers such as vinyl acetate, acrylates, or carbamates, for example, PVODC or the type described in U.S. Patent No. 10,889,736.

[0006] When a silicone-free release polymer is coated to provide a release coating for adhesive tapes, a polymer with a solids content of approximately 3% (w / w) can be used when an organic liquid is used as the carrying liquid. The organic liquid provides a homogeneous and continuous coating on the polymer film.

[0007] However, in the case of these same silicone-free release polymer-based coatings, changing the carrier liquid to water offers regulatory advantages due to reduced VOCs, but a solids content of approximately 20% (w / w) is required to reliably cover the film substrate. This increases the mass of the resulting tape, and the aqueous release coating compositions become significantly less costly compared to their higher-VOC organic liquid counterparts.

[0008] What remains desirable is an aqueous release coating composition for polymer film adhesive tape substrates that can be applied in terms of coating amount to the above-mentioned 3% (w / w) value achievable with organic liquid release coating compositions, and that provides a release coating that does not contain silicone-based release polymers. [Overview of the project]

[0009] This disclosure provides aqueous compositions useful for imparting release properties to adhesive tape substrates. These compositions can be provided in VOC-free form and can provide surfaces or coatings that exhibit excellent release properties even after aging under high humidity. Advantageously, these compositions can be applied in much smaller coating amounts than those required with previously available compositions containing the same release polymer.

[0010] In addition to water and one or more non-silicone release polymers, these compositions contain a low level of superwetter, e.g., more than 0 to 2% (w / w, relative to the total composition). This type of composition can provide a homogeneous coating of the release composition even when the solids content of the composition is far below what was previously actually required.

[0011] Adhesive tape substrates can be coated with compositions containing 14% or less, 12% or less, 10% or less, and even 8% or less of solids (all w / w). This results in a 30-60% reduction in solids content compared to previously available compositions containing the same release polymer.

[0012] The release polymer in the coating composition exhibits good adhesion to the types of substrates most commonly used in articles such as label liners and wrap tapes, both during application and after aging at high humidity and / or low or high temperatures. Furthermore, the release polymer provides good release properties from a wide variety of adhesives, including (but not limited to) natural rubber, acrylic, and hot melt.

[0013] Accordingly, in another embodiment, articles are also provided that include a surface having an adhesive layer and a surface having a release layer provided from such a composition, in contact with the adhesive layer. In tape articles, the adhesive layer and the release layer may be present on opposite sides of the same substrate. In label articles, the adhesive layer may be applied to one substrate, while the release layer may be applied to another substrate, and these two substrates are arranged so that the adhesive layer and the release layer are in direct contact.

[0014] Methods for manufacturing such articles are also provided.

[0015] Other aspects of the present invention will become apparent to those skilled in the art from the following detailed description. To aid in understanding the detailed description, several definitions are provided immediately below. These are intended to apply throughout unless the surrounding text explicitly indicates otherwise. "Comprising" means including (but not limited to) the listed ingredients. "Consisting of" means that the product contains only the listed ingredients and a small amount of inert additives or adjuvants. "Consisting essentially of" means that the product is intended to contain only the listed components and small amounts (less than 5%, 4%, 3%, 2%, 1%, 0.5%, 0.25%, or 0.1% w / v) of other components and / or inert additives or adjuvants that complement the peel properties of the polymer, coating, or LAB and / or provide desirable secondary effects (e.g., oxidation resistance) considering the intended end use. "Polymer" refers to the polymerization product of one or more monomers, and includes homopolymers, copolymers, terpolymers, and tetrapolymers. A copolymer is a polymer containing mer units derived from two reactants, typically monomers, and includes random, block, segmented, and graft copolymers. An "interpolymer" typically refers to a polymer containing mer units derived from at least two reactants, which are monomers, and includes copolymers, terpolymers, tetrapolymers, and the like. A "mer" or "mer unit" refers to a polymer portion derived from a single reactant molecule (for example, an ethylene mer has the general formula -CH2CH2-). "Substituted" means that the group contains a heteroatom or functional group (e.g., a hydrocarbyl group) that does not interfere with the intended purpose of the group. A "polyene" refers to a molecule, typically a monomer, that has at least two double bonds located in the longest part or chain, and specifically includes dienes, trienes, and the like. "Polydiene" refers to a polymer that contains mer units derived from one or more dienes. "Release agent" means a compound or mixture of compounds that is designed or intended to allow the adhesive to be smoothly and controllably peeled from the surface to which the compound is applied without migrating to the adhesive during the peeling process. "Release agent" means a compound or mixture of compounds that is designed or intended to allow the adhesive to be smoothly and controllably peeled from the surface to which the compound(s) is / are applied without migrating to the adhesive during the peeling process. "Release polymer" means a polymeric release agent. "Low adhesion backing size" or "LAB" means a composition comprising at least a coating polymer and a release agent, often in combination with one or more surfactants and other components. "VOC-free" means that when subjected to standard analytical test procedures, volatile organic chemicals are generally less than 0.5 ppm, usually less than 0.25 ppm, typically less than 0.1 ppm, and preferably less than 0.05 ppm. The format element "(thio)" indicates an intention to include the S-containing analog of a compound or group used in connection with this format element. "(Iso)thiocyanate" means a group of the general formula -N=C=O or -N=C=S, or a compound containing such a group. "(Meth)acrylate" means methacrylate or acrylate. "Active hydrogen" means a hydrogen atom that produces methane when a compound containing the H atom is subjected to the Zerewitinoff determination testing. "Lower alkyl" means an alkyl group containing up to 6 carbon atoms. "Long-chain alkyl" means an alkyl group containing at least 12 carbon atoms. A "super wetter" (also known as a "super-spreader") refers to a type of surfactant that, when a single drop is placed on a paraffin surface at room temperature, spontaneously spreads. The term "radical" refers to the part of a molecule that remains after reacting with another molecule, regardless of whether some atoms are gained or lost as a result of the reaction. [Modes for carrying out the invention]

[0016] Detailed explanation As suggested in the overview section above, this composition may contain as few as three components: water, a non-silicone-based release polymer, and up to 2% (w / w) of superwetter.

[0017] The release polymers usable in this composition include polymers containing at least 50%, preferably at least 60%, more preferably at least 70%, even more preferably at least 80%, even more preferably at least 90%, and most preferably at least 99% vinyl acetate or acrylate mer (each of which is in mole percent).

[0018] Because they can provide extremely low-VOC compositions, including VOC-free compositions that do not generate formaldehyde when processed (e.g., dried) under typical manufacturing conditions, the polymers described in U.S. Patent No. 10,889,736 are a preferred group of release polymers, including acrylate mers. A summary of the description of these polymers is provided here for ease of reference.

[0019] Polymers of this preferred group include mer units having a pendant group comprising at least two (thio)carbonyl groups and a plurality of further heteroatoms.

[0020] In certain embodiments, one of the multiple (thio)carbonyl moieties of the multiple pendant groups is bonded to two further heteroatoms, one of which is N and the other is selected from O, S, and N.

[0021] In some of these embodiments, the pendant group can be represented by the following general formula: [ka] In the formula, X represents O or S, E represents an O or S atom or an NR' group, where R' is H or a C1-C6 alkyl group, and R 2 represents a lower alkyl, aryl, alkaryl, or aralkyl group (which may optionally contain heteroatoms such as O, provided that no active hydrogen atoms are present), Z represents a divalent (thio)carbonyl-containing group, which further contains two more heteroatoms bonded to the C atom of the (thio)carbonyl moiety, and R 3 This represents a long-chain alkyl group or a larger functional group containing a long-chain alkyl group. Examples of further heteroatoms that may be bonded to the carbonyl atom of the carbonyl moiety in Z include O, S, and N, where at least one of these further heteroatoms is typically N. (The main form of Z depends, to some extent, on the individual characteristics of E and X and the conditions under which the reaction takes place.)

[0022] Preferred polymers containing a pendant group of type (I) can be provided from monomers represented by the following general formula. [ka] Here, R 2 , R 3 E and X are defined as described above, and R 1 It is either H or a methyl group.

[0023] In other embodiments, the pendant group can be represented by the following general formula. [ka] Here, R 3 , X and E are defined as above, n is 0 or 1, and R 4 is a group of a hydrocarbon compound having two isothiocyanate groups with different reactivities, and R 6 is a linking group, for example, a group such as carbonyl, ether, amine, etc. The pendant group of the general formula (II) is the same as that defined by the general formula (I), except that Z and R 3 (from the general formula (I)) are not directly bonded, but are separated by a further linking group instead.

[0024] The polymer containing a pendant group of the type of the general formula (II) can be provided from a monomer represented by the following general formula. [Chemical formula] Here, each of R 3 , R 4 , E and X is defined as above, and R 5 is a polymerizable group, which is optional, but typically is bonded to an adjacent E atom via a linear or cyclic linking group, for example, a -R 2 XC(X)- group.

[0025] Regarding the polymer defined by the general formula (II-a), there is one obtained from a two-step reaction scheme. Diisothiocyanates having isothiocyanate groups with different reactivities, for example, isophorone diisocyanate (IPDI), 2,4-toluene diisocyanate (2,4-TDI), etc., and their respective sulfur analogs, are reacted with a compound containing two EH groups (however, when E is NR', in order to prevent interference reactions, R' is preferably not H). One of the EH groups contains a polymerizable functional group, and the other contains a long-chain alkyl group (or a larger functional group containing a long-chain alkyl group), for example, specifically a substituted or unsubstituted alkyl group of C15-C25, preferably C16-C20, more preferably C17-Cz8.

[0026] Non-limiting examples of the first type of EH group-containing compound include those represented by the following general formula. [ka] Here, R 1 , R 2 n, E and X are defined as above, R 7 is a phenyl group or a C1-C6 alkyl group. (In certain embodiments, R 2 (Is preferably a C1-C6 alkyl group).

[0027] One subset of compounds of general formula (III-b) where n is 0 is defined by the following general formula, R 7 These are substituted styrenes, including those in which the group is a phenyl group. [ka] Here, E is defined as described above. Variations of this formula are also possible, and for example, α-methylstyrene analogs of compounds of general formula (III-b-1) are expected to be useful, such as compounds in which the EH group is indirectly bonded to the styrene ring, for example, via a hydrocarbyl linking group.

[0028] Another subset of compounds of the type of general formula (III-b) where n is 0 is vinyl alcohol / ether, i.e., R 7 The compound is of general formula (III-b), wherein E is a lower alkyl group, preferably a C1-C3 alkylene group, more preferably a C1-C2 alkylene group. Embodiments of these compounds with sulfur and amine analogs, i.e., where E is S or NR', are also being considered.

[0029] One subset of compounds of the type of general formula (III-b) where n is 1 is a diol vinyl ether, i.e., where X is an O atom and R 7The compound is of general formula (III-b), wherein is a lower alkylene group, preferably a C1-C4 alkylene group. Sulfur and amine analogues of these compounds, i.e., embodiments in which E is S or NR', and their analogues in which X is S, are also intended.

[0030] A non-limiting example of a second type of EH group-containing compound is R 3 And R is defined as E above. 3 -Examples include those defined by EH.

[0031] Other preferred polymers include mer units having pendant groups represented by the following general formula. [ka] Here, X, n, Z, R 3 and R 7 It is defined as described above.

[0032] Polymers containing a pendant group of type (IV) can be provided from monomers represented by the following general formula, wherein all variables are defined as above. [ka] Here, the main form of Z depends to some extent on the individual properties of E and X and the conditions under which the reaction takes place. Polymers obtained from the polymerization of compounds of the type of general formula (IV) have a hydrocarbon main chain having multiple pendant groups as defined by general formula (IV).

[0033] As one specific non-limiting example, consider a compound of general formula (III-b-1) as R 3 -NCX compound (R 3 And X (defined as above) can be reacted to provide a monomer represented by the following general formula. [ka] Here, E, X and R 3It is defined as above. R 3 - Reaction products with NCX compounds and various other compounds of general formula (III-b) are also possible.

[0034] In certain embodiments, each X in the above general formulas can be an oxygen atom.

[0035] The preparation of each of these types of polymers is described in U.S. Patent No. 10,889,736, which was referenced earlier. The polymerization may be homopolymerization and may include two or more such compounds, or may include one or more comonomers, such as polyenes, particularly conjugated dienes, and vinyl compounds, particularly (meth)acrylates and their derivatives, which may participate in emulsion polymerization and may be radically initiated. Comonomers containing long-chain alkyl pendant groups and / or which do not increase or substantially decrease the glass transition temperature (Tg) and / or melt temperature (Tm) of the resulting interpolymer are preferred.

[0036] The mole percentage of mers derived from one or more pendant groups containing the carbamate moiety described above is at least 33%, generally at least 50%, 55%, 60%, or 65%, usually at least 67% or 70%, and typically at least 75% or more. The mole percentage of mers derived from the release polymer of the present invention is often at least 80%, 85%, 90%, or 95%.

[0037] The VOC content of such polymers is generally less than 5 ppm, typically less than 3 ppm, more typically less than 2 ppm, and usually less than 1 ppm. In many embodiments, the polymers are VOC-free.

[0038] Regardless of the individual monomers used to produce the release polymer, the product of emulsion polymerization is typically an aqueous dispersion of the polymer, having a mass-average molecular weight (Mw) on the order of 125 ± 75 kg / mol, usually 125 ± 50 kg / mol, and typically 125 ± 25 kg / mol.

[0039] Emulsion polymerization of release polymers can generally have a solids content of about 15 to about 75% (w / w), preferably about 20 to about 70% (w / w), with a solids content of about 25 to 65% (w / w) being preferred. Maximizing the solids content is usually desirable and can be facilitated by a polymodal particle size distribution. Second or subsequent particle sizes can be produced by introducing a seed polymer, adding an excess of emulsifier, or adding mini-emulsions.

[0040] The release polymer can be used in the form of an aqueous dispersion, or it can be recovered and further processed. It is not necessary to remove surfactants, initiators, chain transfer agents, etc., before such further processing.

[0041] As described above, the compositions of the present invention contain solids of ≤14%, ≤12%, ≤10%, and even ≤8% (all w / w), so that the products of a typical emulsion polymerization can be diluted with water to achieve the desired solids content.

[0042] In addition to water and one or more non-silicone-based release polymers, the composition of the present invention contains one or more superwetters ranging from more than 0% (w / w) to 2% (w / w).

[0043] In certain embodiments, the amount of superwetter(s) (one or more) can be at least 0.25% (w / w). Preferred amounts include 0.1-1.5%, 0.5-1.5%, and particularly 0.75-1.25% (all based on the total mass of the composition, w / w).

[0044] The values ​​and ranges in the preceding paragraph apply to superwetters having a molecular weight similar to that of dioctyl sulfosuccinate (DOSS), i.e., superwetters with a mass mol of approximately 450 g / mol ± 20%. For superwetters with higher molecular weights (e.g., polyoxyethylene (20) sorbitan monooleate, with a mass mol of approximately 1300 g / mol) or lower molecular weights (e.g., myristyldimethylamine oxide, with a mass mol of approximately 250 g / mol; lauryldimethylamine oxide, with a mass mol of approximately 230 g / mol; and 1-octyl-2-pyrrolidone, with a mass mol of approximately 200 g / mol), the mass percentage values ​​and ranges can be appropriately adjusted to give the composition approximately equimolar amounts of one or more superwetters.

[0045] It has been found that including the above-mentioned amount of superwetter (one or more types) in the composition improves the appearance and peelability of the coating provided by that composition. For example, a composition with a solids content of 10% (w / w) but without superwetter exhibits significant de-wetting during application, while the same composition containing a small amount (e.g., 0.5% (w / w)) of superwetter exhibits little to no de-wetting. Furthermore, surprisingly, the sound emitted during the process of peeling the adhesive tape from its roll can be significantly reduced from a zippy sound (which may require ear protection for workers in industrial environments) to a much lower volume.

[0046] While we do not wish to be bound by theory, it is thought that including a superwetter in the above aqueous composition may reduce the number and / or size of substrate areas that are not covered by the release coating (during water evaporation and coalescence of the coating). Bare substrates are thought to cause a slipsticking phenomenon that generates noise during release, i.e., when the PSA roll is unwound.

[0047] Even at low concentrations, SuperWetter significantly reduces the surface tension of aqueous compositions, facilitating their dispersion across hydrophobic surfaces and, in some cases, reducing the amount of time required to achieve such dispersion and / or make the surface superhydrophilic. This ability is thought to be based on its ability to pack very effectively onto surfaces.

[0048] Non-limiting examples of compounds that can be considered superwetters include silicone polyether copolymers (various molecular weights and structures), geminisilicone surfactants, acetylene diols, certain fluorosurfactants, organosilicones, trisiloxane-based surfactants, carbosilanes, fluoroorganic surfactants, alkoxylated acetylene glycols, and hydroxythioethers. See U.S. Patent Nos. 10,552,557, 10,485,739, 10,456,766, 10,415,000, 9,834,699, 8,648,211, 7,264,885, 7,160,373, 6,926,766, 6,645,392, 6,566,322, 6,495,058, 6,475,953 and 6,407,042.

[0049] Of particular interest in relation to the release polymers described above is the superwetter, which is neither silicone-based (i.e., containing siloxane groups) nor fluorine-based (i.e., containing F atoms).

[0050] SuperWetter is commercially available under product names such as Silwet (trademark) (Momentive; Waterford, New York), Dowsil (trademark) (Dow; Midland, Michigan), Surfynol (trademark) and Dynol (trademark) (Evonik; Essen, Germany), Ammonyx (trademark) (Stepan; Northfield, Illinois), Tween (trademark) (Croda Intl.; East Yorkshire, UK), and Easy-Wet (trademark) (Ashland; Wilmington, Delaware).

[0051] Clear improvements in coating properties and noise during peeling were observed when using sulfosuccinates (e.g., DOSS), C12-C16 alkylamine oxides such as myristyldimethylamine oxide, polysorbates, and mixtures of 1-undecanol, sodium lauryl sulfate, 1-octyl-2-pyrrolidone, and ethoxylated undecanol.

[0052] Particularly interesting coating compositions include those described below in the Examples section. Specific superwetters used in the Examples include DOSS, polysorbate (which is non-toxic and considered edible, making it particularly interesting for end uses including food contact and packaging), amine oxide (optionally, in the presence of additives such as antioxidants to suppress possible yellowing of the superwetter), and 1-alkyl-2-pyrrolidone.

[0053] Advantageously, the aqueous compositions of the present invention, useful for imparting release properties to adhesive tape substrates, can be processed and used in the same way as other compositions based on aqueous deliverable release polymers. Various substrates, such as various papers, foils, and polymer films, can be coated using standard commercial conditions, coating thickness, coating speed, etc.

[0054] The release coatings provided by this composition can be used in conjunction with various adhesives, typically pressure-sensitive adhesives (PSAs), including one or more polymers such as natural rubber, butyl rubber, vinyl ether, various acrylates, polyene mers, particularly polydienes such as 1,3-butadiene and isoprene, block copolymers (e.g., SBS, SIS, etc.), random copolymers (e.g., SBR, etc.), and silicone rubber. The foregoing should be considered illustrative and not limiting, and the release polymers of the present invention have been shown to function well with many types of adhesives.

[0055] While various embodiments of the present invention have been provided, they are presented as examples only and are not limiting. To the extent feasible, the above features and embodiments can be individually combined with other features and embodiments, provided that they do not interfere with or conflict with each other.

[0056] The relevant portions of the above text or the documents specifically referenced in the following embodiments are incorporated herein by reference.

[0057] The following non-limiting exemplary embodiments provide readers with detailed conditions and materials useful for carrying out the present invention. [Examples]

[0058] Unless otherwise specified, all chemicals used in the following examples are available from common chemical suppliers, such as Sigma-Aldrich Co. (St. Louis, Missouri).

[0059] A series of aqueous coating compositions with 10% (w / w) solids content were prepared from Suncryl® HP 114 acrylate polymer emulsion (OMNOVA Solutions Inc.; Beachwood, Ohio). Various amounts (0.1–1.0% by mass) of DOSS Superwetter were added to these compositions.

[0060] Alicoats of these compositions were applied to a 0.051 mm (2 mil) thick PET film using a 0# rod, and then dried at approximately 116°C (240°F) for approximately 120 seconds.

[0061] Next, these coated films were laminated to the adhesive surface of film tape tesa® 7475 acrylic adhesive tape (tesa tape inc.; Charlotte, North Carolina).

[0062] The coated test film (tape laminate) was aged (heat-conditioned) for approximately 16 hours at a constant temperature of 65°C and a relative humidity of 60%.

[0063] Strips of self-winding tape material, cut to approximately 2.54 cm (1 inch) wide and 12 cm (5 inches) long, were laminated without heat using a 2.54 cm wide double-coated adhesive paper tape applied to the peeling surface of the test strip. The attached test strip was rolled twice on a working platen using a 2 kg rubber roller moving at a speed of approximately 0.005 m / sec (1 foot / min).

[0064] Each test film was evaluated using the Pressure Sensitive Tape Council's method for peeling and bonding pressure-sensitive tapes (PSTC-101, revised 05-2007, test methods A (180° peel) and F (90° peel)). The obtained peel test values ​​are a quantitative measure of the force required to peel a flexible adhesive tape from a predetermined release material coating at a specific angle and peel speed.

[0065] In the test hereafter referred to as 101-A, a strip of adhesive tape was peeled from a release-coated material at a 180° angle and a speed of 0.005 m / s (1 foot / min). The force required to remove the adhesive from the release coating was measured over a 5-second data acquisition period.

[0066] In the test hereafter referred to as 101-F, a strip of adhesive tape was peeled from a release-coated material at a 90° angle and a speed of 0.255 m / s (50 feet / min). The force required to remove the adhesive from the release coating was measured over a 5-second data acquisition period.

[0067] In the test referred to below as 101-E, so-called post-adhesion evaluation was performed using method E of PSTC-101.

[0068] The test results are listed in Table 1, and the letters represent the following samples (the numbers in parentheses represent the mass percentage of DOSS included): A (1%) - Very good clear coating with minimal edge crawling. B (0.75%) - A good clear coating with slightly more edge crawling than A. C (0.5%) - A clear coating with more edge crawling than B, and slight warbling ("orange peel") near the edges. D (0.25%) - Edge crawling is noticeable, and there are many small dewetting spots during drawdown. E (0.1%) - Edge crawling is similar to D, but with a larger area of ​​dewetting. The column labeled "Sound" was decided subjectively: Z (zippy) - A tearing sound. SZ (slightly zippy) - A controlled, tearing sound. VSZ (Very Slightly Zippy) - A slight tearing sound can be heard. SS (Vague) - It doesn't make a tearing sound, but it can be heard from a short distance away. VSS (Very Low Sound) - Audible at close range. [Table 1]

[0069] The above tests were repeated with different peel-off coatings, Suncryl® CL 223B (OMNOVA Solutions), and different total solids content (20% instead of 10%).

[0070] The results of these tests are listed in Table 2, and the letters represent the following samples: F - Super Wetter 0% G - Super Wetter 0.25% H - Super Wetter 0.5% I - Super Wetter 0.75% [Table 2]

[0071] From the above, it can be seen that by including a small amount of super wetter in the aqueous coating composition, it is possible to provide a release coating that improves release properties and reduces the amount of noise emitted during the process of peeling the adhesive tape from the roll.

[0072] In both of the above series of tests, using DOSS as a super wetter allows for a direct comparison of the two types of release coating compositions. However, this should not be considered limiting, and other types of super wetters are expected to show similar trends at similar additive levels.

[0073] A series of aqueous coating compositions were prepared from Suncryl® HP 114 acrylate polymer emulsion, each with a solid content of 10% (w / w). These included a control sample (J, 32.70%) without superwetter and four samples containing 1% (w / w) superwetter, i.e. K - Surfynol (trademark) AS 5120 humectant (33.60%) L-Tween(trademark) 80 Polysorbate (33.24%) M - Easy-Wet (trademark) 20 1-octyl-2-pyrrolidone (32.52%), and N - Ammonyx(trademark) LO Lauramine oxide (33.45%) The following was prepared. (The numbers in parentheses represent the total solids content of the coating composition.)

[0074] Alicoates of these compositions were applied to a 0.051 mm (2 mil) thick PET film using a #3 rod. The drawdown of samples K and M was well coated with minimal edge crawling, and the drawdown of samples L and N was well coated with very little edge crawling. In contrast, the drawdown of control sample J was clearly coated, but a 0.5 cm dewetting area was present throughout. Each sample was dried at approximately 116°C (240°F) for approximately 120 seconds.

[0075] Next, these coated films were laminated to the adhesive surface of film tape tesa® 7475 acrylic adhesive tape.

[0076] The coated test film (tape laminate) was aged (heat-conditioned) for approximately 16 hours at a constant temperature of approximately 49°C (120°F) and a relative humidity of 50%.

[0077] Each test was performed three times for each sample, and the mean and standard deviation of those tests are recorded in Tables 3a and 3b. [Table 3] [Table 4]

[0078] The SuperWetters tested, each at 1% (w / w), showed significant improvement in the relevant adhesion tests. However, they could not improve the noise emitted during the peeling process of the adhesive tape from its roll to the same extent as DOSS. Some embodiments of the present invention are shown below. [Embodiment 1] A method for providing a release coating to an article, the method comprising applying an aqueous composition comprising at least one release polymer and at least one super wetter in an amount of more than 0% by mass to 2% by mass relative to the composition to a substrate, provided that the composition does not contain a silicone-based release polymer. [Embodiment 2] The method according to Embodiment 1, wherein the composition has a total solids content of 14 percent by mass or less. [Embodiment 3] The method according to Embodiment 2, wherein the total solids content is 12 percent by mass or less. [Embodiment 4] The method according to Embodiment 3, wherein the total solids content is 10 percent by mass or less. [Embodiment 5] The method according to Embodiment 4, wherein the total solids content is 8 percent by mass or less. [Embodiment 6] The method according to any one of Embodiments 1 to 5, wherein the at least one release polymer comprises a polymer having at least 50 mole percent of an acrylate mer. [Embodiment 7] The method according to Embodiment 6, wherein the at least one release polymer is a polymer having at least 50 mole percent of an acrylate mer. [Embodiment 8] The method according to any one of embodiments 6 to 7, wherein at least a portion of the acrylatemer comprises a pendant group having at least two (thio)carbonyl groups and a plurality of further heteroatoms. [Embodiment 9] The method according to any one of Embodiments 1 to 5, wherein the at least one release polymer comprises a polymer having at least 50 mole percent of vinyl acetate. [Embodiment 10] The method according to Embodiment 9, wherein the at least one release polymer is a polymer having at least 50 mole percent of vinyl acetate. [Embodiment 11] The method according to any one of Embodiments 1 to 10, wherein each polymer of the at least one release polymer has a mass-average molecular weight of 125 ± 25 kg / mol. [Embodiment 12] The method according to any one of Embodiments 1 to 11, wherein the composition comprises at least 0.25 mass percent by the composition of at least one superwetter. [Embodiment 13] The method according to Embodiment 12, wherein the composition comprises at least one superwetter in an amount of 0.1 to 1.5 mass percent relative to the composition. [Embodiment 14] The method according to Embodiment 13, wherein the composition comprises at least one superwetter in an amount of 0.75 to 1.25 mass percent relative to the composition. [Embodiment 15] The method according to any one of Embodiments 1 to 14, wherein each of the at least one superwetters does not contain a siloxane group or an F atom. [Embodiment 16] The method according to Embodiment 15, wherein the at least one superwetter comprises sulfosuccinate. [Embodiment 17] The method according to Embodiment 16, wherein the at least one superwetter is sulfosuccinate. [Embodiment 18] The method according to any one of embodiments 16 to 17, wherein the sulfosuccinate is dioctyl sulfosuccinate. [Embodiment 19] A peelable coating provided by the method described in any one of Embodiments 1 to 18. [Embodiment 20] An article comprising a substrate having the peel-off coating described in Embodiment 19. [Embodiment 21] Furthermore, the article according to embodiment 20, further comprising a layer of adhesive. [Embodiment 22] An aqueous composition useful for providing peelability to a coated substrate, wherein the composition has a total solids content of 14% by mass or less and comprises the following: a) A release polymer component that does not contain a silicone-based release polymer and contains at least one release polymer, wherein the at least one release polymer contains at least 50 mol% acrylate or vinyl acetate mer and has a mass average molecular weight of 125 ± 75 kg / mol, and b) At least one sulfosuccinate in an amount of 0.1 to 1.5% by mass relative to the composition. [Embodiment 23] A release coating that does not contain a silicone-based release polymer, wherein the release coating comprises (a) at least one sulfosuccinate and (b) at least one release polymer having a mass-average molecular weight of 125 ± 75 kg / mol and containing at least 50 mol% of an acrylate or vinyl acetate mer, and the release coating is provided from a composition having a total solids content of 14% by mass or less and containing 0.1 to 1.5% by mass of the at least one sulfosuccinate. [Embodiment 24] The release coating according to Embodiment 23, wherein the at least one sulfosuccinate is dioctyl sulfosuccinate, the at least one release polymer comprises at least 50 mol% acrylatemer, at least a portion of the acrylatemer comprises a pendant group comprising at least two (thio)carbonyl groups and a plurality of further heteroatoms, and the composition has a total solids content of 10% by mass or less. [Embodiment 25] An aqueous composition for providing peelability to a coated substrate, wherein the composition does not contain polysiloxane and comprises the following: a) A release polymer component that does not contain a silicone-based release polymer and contains at least one release polymer, wherein the at least one release polymer contains at least 50 mol% acrylate or vinyl acetate mer and has a mass average molecular weight of 125 ± 75 kg / mol, and b) At least one superwetter containing more than 0 mass% and up to 2 mass%, which does not contain siloxane groups or F atoms. [Embodiment 26] The aforementioned Super Wetter Amine oxide, Polysorbate, 1-alkyl-2-pyrrolidone, or A mixture of 1-undecanol, sodium lauryl sulfate, 1-octyl-2-pyrrolidone, and ethoxylated undecanol. A composition according to Embodiment 25, selected from the above. [Embodiment 27] A release coating that does not contain a silicone-based release polymer, wherein the release coating comprises (a) at least one superwetter that does not contain siloxane groups or F atoms, and (b) at least one release polymer that comprises at least 50 mole percent of acrylate or vinyl acetate mer and has a mass average molecular weight of 125 ± 75 kg / mol, and the release coating is provided from a composition comprising more than 0 mass% to ~2 mass% of the at least one superwetter. [Embodiment 28] The aforementioned Super Wetter Amine oxide, Polysorbate, 1-alkyl-2-pyrrolidone, or A mixture of 1-undecanol, sodium lauryl sulfate, 1-octyl-2-pyrrolidone, and ethoxylated undecanol. A peel-off coating as described in Embodiment 27, selected from the above. [Embodiment 29] Articles comprising a substrate having a peel-off coating as described in any one of embodiments 23-24 and 27-28. [Embodiment 30] Furthermore, the article according to embodiment 29, further comprising a layer of adhesive.

Claims

1. A release coating that does not contain a silicone-based release polymer, wherein the release coating comprises (a) at least one superwetter that does not contain siloxane groups or F atoms, and (b) at least one release polymer that contains at least 50 mole percent of acrylate or vinyl acetate and has a mass average molecular weight of 125 ± 75 kg / mol, and the release coating is provided from an aqueous composition containing more than 0% by mass to 2% by mass of the at least one superwetter. The aforementioned at least one type of super wetter, At least one type of sulfosuccinate, Amine oxide, Polysorbate, 1-alkyl-2-pyrrolidone, and A mixture of 1-undecanol, sodium lauryl sulfate, 1-octyl-2-pyrrolidone, and ethoxylated undecanol. A peel-off coating, chosen from among many options.

2. The peel-off coating according to claim 1, wherein the composition has a total solids content of 14 percent by mass or less.

3. The peel-off coating according to claim 2, wherein the total solids content is 12 percent by mass or less.

4. The release coating according to any one of claims 1 to 3, wherein the at least one release polymer comprises a polymer having at least 50 mole percent of an acrylate mer.

5. The release coating according to any one of claims 1 to 4, wherein the at least one release polymer comprises a polymer having at least 50 mole percent of vinyl acetate.

6. The release coating according to any one of claims 1 to 5, wherein the composition comprises at least 0.25 mass percent of the at least one superwetter relative to the composition.

7. The peel coating according to any one of claims 1 to 5, wherein the composition comprises 0.1 to 1.5 mass percent of the at least one superwetter relative to the composition.

8. The peel-off coating according to claim 1, wherein the at least one sulfosuccinate is dioctyl sulfosuccinate.

9. The release coating according to claim 1, wherein the at least one superwetter comprises at least one sulfosuccinate, and the release coating is provided from a composition having a total solids content of 14% by mass or less and containing 0.1 to 1.5% by mass of the at least one sulfosuccinate.

10. The peel coating according to claim 9, wherein the at least one sulfosuccinate is dioctyl sulfosuccinate, the at least one peel polymer comprises at least 50 mol% acrylatemer, at least a portion of the acrylatemer comprises a pendant group comprising at least two (thio)carbonyl groups and a plurality of further heteroatoms, and the composition has a total solids content of 10% by mass or less.

11. An article comprising a substrate having a peel-off coating according to any one of claims 1 to 10.

12. Furthermore, the article according to claim 11, further comprising a layer of adhesive.

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