Nail coating based on photocurable composition

Abstract

To provide a nail coating obtained from a specific photocurable composition which contains an impact-modified core / shell copolymer and has enhanced mechanical properties and durability, a method for forming a nail coating from such a photocurable composition, an article including a container containing such a photocurable composition and a kit including a packaged photocurable composition and instructions for preparing a nail coating from the same.SOLUTION: There is provided a photocurable composition which comprises a) at least one (meth)acrylate-functionalized monomer, b) at least one (meth)acrylate-functionalized oligomer, c) particles of at least one core / shell copolymer and d) at least one photoinitiator and is useful for forming an impact resistant coating having durability to nails.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to nail coatings obtained from certain photocurable compositions comprising impact-modified core / shell copolymers and having enhanced mechanical properties and durability, methods of forming nail coatings from such photocurable compositions, articles comprising containers containing such photocurable compositions, and kits comprising packaged photocurable compositions and instructions for making nail coatings therefrom.

Background Art

[0002] Acrylic nail formulations are well-known and can be useful for improving the appearance of nails (e.g., human fingernails and toenails) by allowing the user to mold the formulation into various shapes. Conventional acrylic nail formulations consist of two parts: 1) a photocrosslinkable liquid monomer and 2) an acrylic polymer powder containing an activator / initiator. The two components are mixed together and applied to the nails and are shaped and carved by a nail technician using various tools. Acrylic nails made with such conventional formulations can be brittle and have low impact strength. Impact resistance is important in the context of nail decoration because consumers expect acrylic nails to be durable and able to withstand external forces for an extended period without cracking, breaking, chipping, or otherwise deteriorating in appearance.

[0003] In recent years, a new type of nail formulation that is a one-component system containing a photo-curable oligomer, a photo-curable monomer, a pigment, and optionally one or more other additives has been developed. Such formulations typically have a viscosity similar to that of conventional nail polish liquids, are applied to the surface of the nail in much the same way as conventional nail polish liquids, are cured in situ using ultraviolet (UV) light, and can generally provide a protective / decorative coating that can last up to 14 days. Such formulations can be referred to as "UV gel polish" and are described, for example, in U.S. Patent No. 8,901,199 (B2), U.S. Patent No. 8,367,742 (B2), and U.S. Patent No. 9,084,738 (B2). Hybrid variants based on UV gel polish and conventional acrylic nail formulations have been disclosed, where the UV gel polish formulation is supplemented with a polymer powder such as a powder based on polymethyl methacrylate (PMMA). Such powders have a particle size of at least 1 micron (i.e., at least 1000 nm). See, for example, U.S. Patent No. 6,244,274 (B2), U.S. Patent Application Publication No. 2018 / 0092827 (A1), and WO2017 / 217983A1.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

[0005] Despite such advancements in nail coating technology, there is still a need for improved formulations that provide nail coatings with enhanced durability and resistance to external forces such as impact when cured.

Means for Solving the Problem

[0006] The present invention utilizes a photocurable composition comprising at least the following components: a) at least one (meth)acrylate-functionalized monomer; b) at least one (meth)acrylate-functionalized oligomer; c) at least one core / shell copolymer particle; d) at least one photoinitiator Such a composition may be transparent or colored and is formulated to be used as a one-component system, i.e., the formulation can be applied to the nail surface without the need to mix a first component with a second component and then cured by exposure to actinic radiation (e.g., UV light or visible light). By including core / shell copolymer particles in the photocurable composition, the mechanical properties and durability of the resulting nail coating can be significantly improved compared to cured nail coatings prepared using similar formulations that do not contain such core / shell copolymer particles. Furthermore, because of their small size, these impact-modifying core / shell copolymer particles have little or no effect on the optical transparency of the cured material and cannot be PMMA-based particles larger than 1 micron in size.

[0007]

[0008] The photocurable composition can be formulated to have the following additional attributes or properties: 1) A relatively high viscosity and liquid consistency that allows the composition to be easily applied to the nail surface and shaped into a desired shape of significant thickness without flowing or dripping before photocuring. ​2) It is not necessary to mix with other components before coating and curing. 3) High degree of uniformity and physical stability (for example, when stored for a long time, the components of the composition have little or no tendency to separate). 4) Long open time (enabling a long period during which the nail can be engraved). 5) Low odor. 6) Little shrinkage during curing. 7) High transparency during curing and / or 8) Low content of volatile substances (that is, little or no non-reactive solvent).

[0009] The present invention provides a coating for nails, and the coating is a photocured product of such a photocurable composition.

[0010] Also provided is a method for forming a coating on nails, comprising: a) placing the photocurable composition described herein on the surface of the nail; b) exposing the photocurable composition to actinic radiation, particularly ultraviolet light or visible light. A method comprising the above is provided by the present invention.

[0011] Also provided by the present invention is a packaged article comprising a container and the photocurable composition described herein disposed within the container, the packaged article having a dispensing component capable of dispensing the photocurable composition from the container.

[0012] The present invention further provides a kit comprising a packaged article comprising a container and the photocurable composition described herein disposed within the container, at least one applicator, and instructions for use for dispensing, applying, and curing the photocurable composition to provide a nail coating.

Embodiments for Carrying Out the Invention

[0013] The present invention relates to a) at least one (meth)acrylate-functionalized monomer, and b) at least one (meth)acrylate-functionalized oligomer, and c) particles of at least one core / shell copolymer, and d) at least one photoinitiator A photocurable composition comprising, consisting essentially of, or consisting of these is used.

[0014] One or more further components, in particular pigments and / or colorants, and optionally the (meth)acrylic polymers described in detail hereinafter may further be present. The photocurable composition is used to form a cosmetic coating for nails. The photocurable composition is applied to the surface of the nail (i.e., the nail plate), and then easily shaped (sculpted) into the desired shape on the surface of the nail by a nail technician or other operator, and then exposed to ultraviolet (UV) light or other actinic radiation to photopolymerize the shaped photocurable composition, which can be a liquid having a relatively high viscosity at room temperature that enables the formation of a hard, durable, and impact-resistant nail coating. Alternatively, the photocurable composition can be a liquid having a relatively low viscosity at room temperature that enables the formation of a hard, durable, and impact-resistant nail coating by easily applying the photocurable composition as a thin layer to the surface of the nail (i.e., the nail plate) and then exposing the thin layer of the photocurable composition to ultraviolet (UV) light or other actinic radiation to photopolymerize the thin layer of the photocurable composition. In particular, the presence of the core / shell copolymer particles helps to significantly improve the impact properties (i.e., resistance to chipping, cracking, and scuffing) of the cured coating while maintaining good optical transparency and high gloss for a long time.

[0015] Core / shell copolymer Core / shell copolymers useful in the context of the present invention generally can be described as polymeric materials, typically granular (particle form), consisting of a core (inner part) composed of a first polymer (“core polymer”) and at least one shell (outer part) composed of a second polymer (“shell polymer”) that substantially or completely surrounds the core. Typically, the shell polymer has a glass transition temperature higher than that of the core polymer. The glass transition temperature of the polymers of the core / shell copolymer can be measured according to standard ISO 11357-2:199. Generally speaking, the glass transition temperature of the core polymer is preferably less than 20 °C, less than 10 °C, or less than 0 °C, for example, between -140 °C and 0 °C. Preferably, the glass transition temperature of the shell polymer is more than 20 °C or more than 30 °C, for example, between 30 °C and 250 °C. According to various embodiments of the present invention, the difference in the glass transition temperatures of the core polymer and the shell polymer can be at least 10 °C, at least 20 °C, or at least 30 °C. Thus, the core polymer can be considered a “soft” polymer (and can in fact be elastomeric or rubbery), and the shell polymer can be considered a “hard” (non-elastomeric) polymer.

[0016] The shell portion of the core / shell copolymer, in polymerized form, preferably can contain an alkyl methacrylate having 1 to 12 carbon atoms in the alkyl chain (i.e., C1-C12 alkyl methacrylate), and preferably an alkyl methacrylate having 1 to 4 carbon atoms, such as methyl methacrylate, and / or a vinyl aromatic organic compound having 6 to 12 carbon atoms, such as styrene, and / or acrylonitrile. The shell portion of the core / shell copolymer may or may not be crosslinked.

[0017] The core part of the core / shell copolymer preferably contains, in polymerized form, a conjugated diene (such as butadiene) having 4 to 12, and preferably 4 to 8 carbon atoms, or an alkyl acrylate (such as butyl acrylate) having an alkyl chain with 1 to 12, and preferably 1 to 8 carbon atoms. The alkyl chain may be a straight-chain alkyl chain or a branched alkyl chain.

[0018] The core / shell copolymer may be, for example, a core / shell copolymer having a core containing (in polymerized form) butadiene and a shell containing (in polymerized form) methyl methacrylate, ethyl acrylate, butyl acrylate, methacrylic acid, and / or styrene; a core / shell copolymer having a core containing (in polymerized form) butyl acrylate, n-octyl acrylate, and / or 2-ethylhexyl acrylate and a shell containing (in polymerized form) methyl methacrylate; or a core / shell copolymer having a core containing (in polymerized form) butadiene and a shell containing (in polymerized form) a mixture of acrylonitrile and styrene. In the above-described embodiments, the butadiene constituting the core may be copolymerized with styrene.

[0019] The following types of core / shell copolymers are examples of core / shell copolymers particularly suitable for use in the present invention. a). A core / shell copolymer consisting essentially of or consisting of a core composed of butyl acrylate in a polymerized form (e.g., a homopolymer of butyl acrylate or a copolymer of butyl acrylate and at least one comonomer, the copolymer containing at least 80 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of polymerized butyl acrylate) and a shell composed of methyl methacrylate in a polymerized form (e.g., a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate and at least one comonomer, the copolymer containing at least 80 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of polymerized methyl methacrylate), and b). A core / shell copolymer consisting essentially of or consisting of a core composed of copolymerized styrene and butadiene (e.g., a copolymer of butadiene and styrene, which may be copolymerized with at least one additional comonomer in an amount up to 10% by mass based on the mass of the copolymer) and a shell composed of methyl methacrylate in a polymerized form (e.g., a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate and at least one comonomer, the copolymer containing at least 80 wt%, at least 85 wt%, at least 90 wt%, at least 95 wt%, or at least 99 wt% of polymerized methyl methacrylate).

[0020] The mass of the core is preferably in the range of 10% to 99% of the total mass of the core / shell copolymer, for example, 60% to 95%. The particle size of the core / shell copolymer is less than 1000 nm, preferably between 10 and 900 nm, between 25 and 700 nm, or between 40 and 600 nm.

[0021] Examples of core polymers that may be mentioned include rubber; polysiloxane; homopolymers and copolymers of butadiene, butyl acrylate, methyl methacrylate, ethyl acrylate, 2-ethylhexyl acrylate, and / or butyl acrylate; isoprene homopolymer; isoprene-butadiene copolymer; copolymers of 98% by mass or less of vinyl monomer and isoprene; and copolymers of 98% by mass or less of vinyl monomer and butadiene. The vinyl monomer may be styrene, alkylstyrene, acrylonitrile, alkyl (meth)acrylate, alkyl acrylate, butadiene or isoprene. The core polymer may also contain a siloxane that may be copolymerized with an alkyl acrylate. The core of the core / shell copolymer may be fully or partially crosslinked. To achieve crosslinking, at least bifunctional monomers can be added during the preparation of the core, and these monomers can be selected from poly(meth)acrylic esters of polyols such as butylene di(meth)acrylate and trimethylolpropane trimethacrylate. Other polyfunctional monomers are, for example, divinylbenzene, trivinylbenzene, vinyl acrylate and vinyl methacrylate, and triallyl cyanurate. The core can also be crosslinked therein by introducing unsaturated functional monomers such as unsaturated carboxylic acid anhydrides, unsaturated carboxylic acids and unsaturated epoxides by grafting or as comonomers during polymerization. Examples that may be mentioned include maleic anhydride, (meth)acrylic acid and glycidyl methacrylate. Crosslinking can also be carried out using the inherent reactivity of monomers, such as dienes.

[0022] The core / shell copolymer may include a single shell or multiple shells (i.e., two or more shells that may differ in their monomer composition, molecular weight, degree of crosslinking, or other characteristics). The shell of the core / shell copolymer may be, for example, a homopolymer or copolymer of styrene, alkylstyrene, C1-C4 alkyl (meth)acrylate, methyl methacrylate, butyl acrylate, ethyl acrylate, or a copolymer containing at least 70% by weight of one of the aforementioned monomers and at least one comonomer selected from another of the aforementioned monomers, another alkyl (meth)acrylate, vinyl acetate, and acrylonitrile. The shell can be functionalized by introducing unsaturated functional monomers such as unsaturated carboxylic anhydrides, unsaturated carboxylic acids, and unsaturated epoxides therein, either by grafting or as comonomers during polymerization. Examples that may be mentioned include maleic anhydride, (meth)acrylic acid, glycidyl methacrylate, hydroxyethyl methacrylate, and alkyl (meth)acrylamide. Examples that may be mentioned include core / shell copolymers having a shell made of polystyrene and core / shell copolymers having a shell made of PMMA. The shell may also contain imide functional groups by either copolymerization with maleimide or chemical modification with a primary amine of PMMA. Advantageously, the molar percentage of the imide functional groups is 30% - 60% (relative to the entire shell). It is also possible to use a core / shell copolymer containing two shells, where one shell is made of polystyrene and the other outer shell is made of PMMA. Examples of core / shell copolymers and methods for preparing them are described in U.S. Patent Nos. 4,180,494, 3,808,180, 4,096,202, 4,260,693, 3,287,443, 3,657,391, 4,299,928, 3,985,704, 5,773,520, each of which is hereby incorporated by reference in its entirety for all purposes.

[0023] According to certain embodiments, the core can account for 5% to 95%, 50% to 95%, or 60% to 90% by mass of the core / shell copolymer, and the shell can account for 95% to 5%, 50% to 5%, or 40% to 10% by mass of the core / shell copolymer.

[0024] Polymers referred to in the art as "multi-stage polymers" are also useful as the core / shell copolymer component of the photocurable composition of the present invention. Multi-stage polymers are described, for example, in the published applications of WO 2016 / 102666, US 2017 / 0369696, WO 2017 / 121749, WO 2017 / 121750, WO 2017 / 220791, WO 2018 / 002259, WO 2018 / 002260, WO 2018 / 002273, FR 17 56649, and FR 17 56647, each of which is hereby incorporated by reference in its entirety for all purposes.

[0025] The amount of the core / shell copolymer contained in the photocurable composition can be varied as desired depending on, among other possible factors, the type of core / shell copolymer used, the attributes targeted in the cured nail coating, and the type of polymerizable organic substance used. According to various aspects of the present invention, the photocurable composition can contain at least 1%, at least 5%, or at least 10% by mass of the core / shell copolymer based on the total mass of the photocurable composition. In other aspects, the photocurable composition can contain 50% by mass or less, 45% by mass or less, or 40% by mass or less of the core / shell copolymer based on the total mass of the photocurable composition. Thus, the photocurable composition can be composed of particles of at least one core / shell copolymer, for example, 1 to 50%, 5 to 45%, or 10 to 40% by mass based on the total mass of the photocurable composition.

[0026] According to certain embodiments, the photocurable composition may contain from 1 to 200, 5 to 100, or 15 to 70 parts by mass of the core / shell copolymer per 100 parts by mass of the total mass of the polymerizable organic substances (e.g., the total mass of the polymerized monomers + polymerized oligomers).

[0027] Core / shell copolymers suitable for use in the present invention include core / shell copolymers sold under the brand names Biostrength®, Durastrength®, and Clearstrength® by Arkema.

[0028] An important advantage achieved by the use of the above core / shell copolymers is that such core / shell copolymers show little or no tendency to cloud the cured nail coating prepared from the photocurable composition according to the present invention. Thus, it is possible to formulate a photocurable composition containing such core / shell copolymer particles that can provide a very transparent cured nail coating when photocured, even at relatively high levels of the core / shell copolymer.

[0029] (Meth)acrylic polymer The photocurable composition of the present invention may optionally contain one or more (meth)acrylic polymers. However, such (meth)acrylic polymers are not essential, and photocurable compositions without (meth)acrylic polymers are also contemplated by the present invention. As used herein, the term "(meth)acrylic polymer" means a polymer having no core / shell structure and containing one or more (meth)acrylic monomers (in polymerized form), wherein the (meth)acrylic monomers constitute 50% by mass or more of the (meth)acrylic polymer. As used herein, the term "(meth)acrylic monomer" means any type of polymerizable monomer containing one or more acrylic and / or methacrylic functional groups.

[0030] The presence of the (meth)acrylic polymer in the photocurable composition can help facilitate the dispersion and stabilization of the core / shell copolymer in both the photocurable composition and the cured article prepared therefrom. In the absence of the (meth)acrylic polymer, the core / shell copolymer, typically in the form of particles, may tend to aggregate and settle out of the photocurable composition (making the photocurable composition non-uniform). Thus, including the (meth)acrylic polymer allows the core / shell copolymer to be uniformly dispersed in the photocurable composition, facilitating the formation of a uniform cured article prepared by curing the photocurable composition. An ideal uniform dispersion of the core / shell copolymer in the matrix has no aggregates after the core / shell copolymer is combined with monomers and oligomers (which may sometimes be generally referred to as "polymerizable organic substances"). Thus, a liquid photocurable composition containing a (meth)acrylic polymer, a core / shell copolymer, and a polymerizable organic substance may have or exhibit a better dispersion of the core / shell copolymer than a similar composition without the (meth)acrylic polymer. Further, a liquid photocurable composition containing a (meth)acrylic polymer, a core / shell copolymer, and a polymerizable organic substance may have a lower viscosity than a similar composition without the (meth)acrylic polymer.

[0031] (The molecular weight of the (meth)acrylic polymer is not particularly limited and can be varied as necessary or desired to impart specific features or properties to the photocurable composition and / or the cured article prepared therefrom. The (meth)acrylic polymer may, for example, have a weight average molecular weight of from 2,000 g / mol to 1,000,000 g / mol.

[0032] In a first embodiment, the (meth)acrylic polymer may have a weight average molecular weight (Mw) of at least 100,000 g / mol, greater than 100,000 g / mol, greater than 105,000 g / mol, greater than 110,000 g / mol, greater than 120,000 g / mol, greater than 130,000 g / mol, or greater than 140,000 g / mol.

[0033] (Meth)acrylic polymers may have a weight-average molecular weight (Mw) of less than 1,000,000 g / mol, less than 900,000 g / mol, less than 800,000 g / mol, less than 700,000 g / mol, less than 600,000 g / mol, less than 550,000 g / mol, less than 500,000 g / mol, or less than 450,000 g / mol.

[0034] For example, according to a first preferred embodiment, the weight-average molecular weight (Mw) of the (meth)acrylic polymer (PI) is preferably between 100,000 g / mol and 1,000,000 g / mol, preferably between 105,000 g / mol and 900,000 g / mol, more preferably between 110,000 g / mol and 800,000 g / mol, advantageously between 120,000 g / mol and 700,000 g / mol, more advantageously between 130,000 g / mol and 600,000 g / mol, and most advantageously between 140,000 g / mol and 500,000 g / mol.

[0035] In a second embodiment, the (meth)acrylic polymer has a weight-average molecular weight M w less than 100,000 g / mol, less than 90,000 g / mol, less than 80,000 g / mol, less than 70,000 g / mol, less than 60,000 g / mol, less than 50,000 g / mol, or less than 40,000 g / mol.

[0036] In a second embodiment, the (meth)acrylic polymer may have a weight-average molecular weight (M w ) greater than 2000 g / mol, greater than 3000 g / mol, greater than 4000 g / mol, greater than 5000 g / mol, greater than 6000 g / mol, greater than 6500 g / mol, greater than 7000 g / mol, greater than 10,000 g / mol, or greater than 12,000 g / mol.

[0037] The weight-average molecular weight (M w) may be between 2000 g / mol and 100,000 g / mol, between 3000 g / mol and 90,000 g / mol, between 4000 g / mol and 80,000 g / mol, between 5000 g / mol and 70,000 g / mol, between 6000 g / mol and 50,000 g / mol, or between 10,000 g / mol and 40,000 g / mol.

[0038] According to a specific embodiment of the present invention, the (meth)acrylic polymer may contain at least 50% by mass, at least 60% by mass, or at least 70% by mass of one or more monomers selected from the group consisting of C1-C12 alkyl (meth)acrylates. For example, the (meth)acrylic polymer may contain at least 50% by mass, at least 60% by mass, at least 70% by mass, or at least 80% by mass of one or more monomers selected from C1-C4 alkyl methacrylate monomers, C1-C8 alkyl acrylate monomers, and mixtures thereof.

[0039] In a specific embodiment, the glass transition temperature (Tg) of the (meth)acrylic polymer is 30°C or higher, for example, between 30°C and 150°C. The glass transition temperature of the (meth)acrylic polymer (PI) may be, for example, between 40°C and 150°C, between 45°C and 150°C, or between 50°C and 150°C.

[0040] According to certain embodiments, the (meth)acrylic polymer is not crosslinked. According to other embodiments, the (meth)acrylic polymer is a thermoplastic polymer. The (meth)acrylic polymer may be a homopolymer or a copolymer, and the term "copolymer" refers to a polymer that contains two or more different monomers in polymerized form. As used herein, the term "thermoplastic polymer" means a polymer that becomes liquid or more liquid or less viscous when heated and can take on a new shape by the application of heat and pressure. In certain embodiments, the (meth)acrylic polymer is not grafted to any other polymer, or at least a portion of the (meth)acrylic polymer is not grafted to any other polymer.

[0041] In a first embodiment, the (meth)acrylic polymer comprises 50 wt% to 100 wt%, 80 wt% to 100 wt%, or 80 wt% to 99.8 wt% of methyl methacrylate, and 0.2 wt% to 20 wt% of a C1-C8 alkyl acrylate monomer (in polymerized form). According to certain non-limiting embodiments, the C1-C8 alkyl acrylate monomer may be selected from the group consisting of methyl acrylate, ethyl acrylate, and butyl acrylate.

[0042] In a second embodiment, the (meth)acrylic polymer comprises one or more functional monomers in an amount between 0 wt% and 50 wt% (in polymerized form). For example, the (meth)acrylic polymer may comprise a functional monomer in an amount between 0 wt% and 30 wt%, between 1 wt% and 30 wt%, between 2 wt% and 30 wt%, between 3 wt% and 30 wt%, between 5 wt% and 30 wt%, or between 5 wt% and 30 wt%.

[0043] The functional monomer of the second preferred embodiment may be a (meth)acrylic monomer. The functional monomer has the formula (1) or (2):

[0044]

Chemical formula

[0045] [In the formulae, in both formulae (1) and (2), R1 is selected from H or CH3; in formula (1), Y is O, R5 is H, or an aliphatic or aromatic group having at least one atom that is not C or H; in formula (2), Y is N, and R4 and R3 are independently selected from H or an aliphatic or aromatic group.] can have.

[0046] Preferably, the functional monomer is selected from the group consisting of glycidyl (meth)acrylate, (meth)acrylic acid, (meth)acrylamide such as dimethylacrylamide, 2-methoxyethyl (meth)acrylate, 2-aminoethyl (meth)acrylate (optionally quaternized), (meth)acrylate monomers containing phosphonate or phosphate groups, alkylimidazolidione (meth)acrylate, and polyethylene glycol (meth)acrylate, and combinations thereof. Preferably, the polyethylene glycol group of the polyethylene glycol (meth)acrylate has a number average molecular weight in the range of 400 g / mol to 10,000 g / mol.

[0047] According to a particular embodiment of the present invention, the (meth)acrylic polymer does not contain any functional groups that can participate in the curing / polymerization that occurs when the photocurable composition cures. In such an embodiment, the (meth)acrylic polymer can be considered non-reactive.

[0048] According to certain embodiments of the present invention, the (meth)acrylic polymer may be soluble in an organic polymer substance (a mixture of monomers and oligomers present in the photocurable composition) at 25°C. That is, the organic polymer substance functions as a solvent for the (meth)acrylic polymer. Thus, a combination of the (meth)acrylic polymer, monomers, and oligomers can be a uniform (single-phase) liquid at 25°C. "Soluble" means that when the (meth)acrylic polymer contacts the polymerizable organic substance within a certain period of time, it dissolves to obtain a solution of the (meth)acrylic polymer in the polymerizable organic substance. The solubility of the (meth)acrylic polymer in the polymerizable organic substance can be easily tested by mixing the materials at 25°C with stirring and visually inspecting the mixture.

[0049] When present in the photocurable composition, the (meth)acrylic polymer can be included in any suitable amount, such as up to 80% by weight, up to 70% by weight, up to 60% by weight, up to 50% by weight, up to 40% by weight, up to 30% by weight, up to 20% by weight, up to 10% by weight, or up to 5% by weight, based on the total weight of the photocurable composition.

[0050] Polymerizable organic substance The photocurable composition used in the present invention is composed of a polymerizable organic substance. In this specification, the term "polymerization" means being able to participate in a polymerization or curing reaction to form a polymer structure. The polymerizable organic substance is a monomer and / or oligomer in its structure and can be characterized as containing one, two, three or more polymerizable functional groups per molecule. Preferred polymerizable functional groups include, in particular, functional groups that can participate in chain growth and ring-opening polymerization mechanisms, such as ethylenic and acetylenic unsaturated functional groups (e.g., (meth)acryloyl, vinyl, olefin and alkyne functional groups) and heterocyclic functional groups (e.g., epoxide and oxetane functional groups). Polymerizable functional groups that polymerize via free radical and / or cationic mechanisms are particularly preferred. The polymerizable organic substance may contain multiple types of polymerizable functional groups. The molecular weight of the preferred polymerizable organic substance is not particularly limited, but may be, for example, 120 to 50,000 g / mol or 150 to 25,000 g / mol (when the polymerizable organic substance is an oligomer, "molecular weight" refers to the number average molecular weight determined by gel permeation chromatography using polystyrene calibration standards). Combinations of various polymerizable organic substances are used in the photocurable composition of the present invention. In particular, the photocurable composition contains at least one polymerizable monomer and at least one polymerizable oligomer.

[0051] According to a specific embodiment, the total mass of the oligomer in the photocurable composition is at least about the same as the total mass of the monomer. For example, the mass ratio of polymerizable oligomer:polymerizable monomer can be 50:50 to 90:10.

[0052] According to another embodiment, the total mass of the monomer in the photocurable composition is at least about the same as the total mass of the oligomer. For example, the mass ratio of polymerizable monomer:polymerizable oligomer can be 50:50 to 90:10.

[0053] Preferably, the polymerizable organic substances are combined to be present in the photocurable composition, and the combination is selected such that it is liquid in a temperature range of at least between 0°C and 60°C.

[0054] Suitable exemplary types of polymerizable organic substances include, but are not limited to, epoxides (oxiranes), oxetanes, oxolanes, cyclic acetals, and other cyclic ethers, cyclic lactones, vinyl compounds (both aliphatic and aromatic), cyanoacrylates, (meth)acrylamides, and (meth)acrylates (which are particularly preferred). As used herein, the term "(meth)acrylate" refers to both functional groups of acrylate (-O-C(=O)-CH=CH2) and methacrylate (-O-C(=O)-C(CH3)=CH2).

[0055] The polymerizable organic substance includes at least one moiety capable of participating in a polymerization or curing reaction, whereby a plurality of polymerizable organic substance molecules covalently bond to each other to form a polymer structure. Suitable reactive moieties include ethylenically unsaturated sites (i.e., carbon-carbon double bonds, C=C). Such ethylenically unsaturated sites can be provided, for example, by (meth)acryloyl, maleyl, allyl, propenyl, and / or vinyl groups. As used herein, the term "(meth)acryloyl" is intended to include both methacryloyl and acryloyl, as found in (meth)acrylates and (meth)acrylamides.

[0056] As described above, suitable ethylenically unsaturated functional groups for use in the polymerizable organic substances of the photocurable composition include groups containing a carbon-carbon double bond, in particular a carbon-carbon double bond in which at least one carbon is capable of participating in a reaction (e.g., a free radical reaction) that covalently bonds to an atom, particularly a carbon atom, within a second molecule. Such a reaction can thereby result in the polymerization or curing of an organic substance containing one or more ethylenically unsaturated functional groups such that it becomes part of a polymer matrix or polymer chain. The carbon-carbon double bond can be present, for example, as part of an α,β-unsaturated carbonyl moiety, such as an α,β-unsaturated ester moiety like an acrylate functional group (H2C=CH-C(=O)O-) or a methacrylate functional group (H2C=C(CH3)-C(=O)O-). The carbon-carbon double bond can also be present in an ethylenically unsaturated functional group in the form of a vinyl group -CH=CH2 or an allyl group -CH2-CH=CH2.

[0057] In certain embodiments, the photocurable composition used in the present invention is characterized by comprising at least one (meth)acrylate-functionalized organic substance. The (meth)acrylate-functionalized organic substance can be described as an organic substance bearing one or more (meth)acrylate functional groups per molecule. As used herein, the term “(meth)acrylate” refers to both acrylate and methacrylate functional groups. Suitable (meth)acrylate-functionalized organic substances for use in the present invention generally include an ethylenically unsaturated organic substance (a compound containing at least one α,β-unsaturated ester moiety) containing a carbon-carbon double bond that can participate in a reaction initiated by at least one carbon-carbon double bond alpha to an ester group, particularly a free radical reaction, particularly a reaction initiated by ultraviolet radiation or electron beam radiation. Such a reaction can thereby result in the polymerization or curing of the (meth)acrylate-functionalized organic substance to become part of the polymerization matrix or polymer chain. In various embodiments of the present invention, the (meth)acrylate-functionalized organic substance can contain one, two, three, four, five or more (meth)acrylate functional groups per molecule. Combinations of multiple (meth)acrylate-functionalized organic substances containing varying numbers of (meth)acrylate groups can be utilized in the photocurable composition of the present invention.

[0058] Accordingly, the photocurable composition used in the present invention can comprise one or more (meth)acrylate-functionalized organic substances that are capable of undergoing free radical polymerization (curing) initiated by exposure to actinic radiation (e.g., ultraviolet light) or electron beam radiation. The (meth)acrylate-functionalized organic substance can be an oligomer or a monomer, or preferably, a combination of an oligomer and a monomer.

[0059] Any of the following types of (meth)acrylate-functionalized organic substances can be used, for example, in the photocurable composition of the present invention, optionally or optionally, in combination with one or more other types of polymerizable organic substances as co-reactants: (meth)acrylate esters of aliphatic monoalcohols, (meth)acrylate esters of alkoxylated aliphatic monoalcohols, (meth)acrylate esters of aliphatic polyols, (meth)acrylate esters of alkoxylated aliphatic polyols, monomers such as (meth)acrylate esters of aromatic ring-containing alcohols; and (meth)acrylate esters of alkoxylated aromatic ring-containing alcohols; and oligomers such as epoxy (meth)acrylate, polyether (meth)acrylate, urethane (meth)acrylate, polyester (meth)acrylate (including their amine and sulfide-modified derivatives); and combinations thereof.

[0060] According to one aspect of the present invention, the photocurable composition contains at least one hydroxyalkyl (meth)acrylate such as hydroxyethyl methacrylate and / or hydroxypropyl methacrylate. For example, the photocurable composition may contain a total of 5 to 30% by mass of hydroxyalkyl (meth)acrylate based on the total mass of the polymerizable organic substances in the photocurable composition. However, in other embodiments, since at least some hydroxyalkyl (meth)acrylates have sensitizing properties, the photocurable composition may contain little or no hydroxyalkyl (meth)acrylate (for example, less than 5% by mass or less than 0% by mass based on the total mass of the polymerizable organic substances).

[0061] According to another aspect of the present invention, the photocurable composition contains at least one cycloalkyl (meth)acrylate, particularly isobornyl (meth)acrylate. For example, the photocurable composition may contain 1 to 25% by mass or 5 to 15% by mass of cycloalkyl (meth)acrylate (e.g., isobornyl methacrylate) based on the total mass of the polymerizable organic substances in the photocurable composition. Cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and cyclic trimethylolpropane formal (meth)acrylate represent other types of cycloalkyl (meth)acrylate useful in the present invention.

[0062] According to another aspect of the present invention, the photocurable composition contains at least one ethylene glycol or polyethylene glycol-based (meth)acrylate such as poly(ethylene glycol) di(meth)acrylate. Such substances may be described as (meth)acrylates of ethylene glycol and polyethylene glycol, and polyethylene glycol may contain two or more oxyethylene units derived from ethylene oxide per molecule. In certain embodiments, the substance contains an ethylene glycol segment or a polyethylene glycol segment having a number average molecular weight of about 100 g / mol to about 1000 g / mol. Such a segment has a structural formula -(CH2CH2O) n- may coincide. For example, the photocurable composition may contain 1 to 80% by mass or 5 to 60% by mass of poly(ethylene glycol) di(meth)acrylate based on the total mass of the polymerizable organic substances in the photocurable composition. Ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, PEG-9 di(meth)acrylate (containing on average about 9 oxyethylene units per molecule), PEG200 di(meth)acrylate (containing a polyethylene glycol segment with a number average molecular weight of about 200 g / mol), and PEG600 di(meth)acrylate (containing a polyethylene glycol segment with a number average molecular weight of about 600 g / mol) represent other types of ethylene glycol or poly(ethylene glycol)-based (meth)acrylates that are useful in the present invention. The use of such ethylene glycol or poly(ethylene glycol)-based (meth)acrylates in the photocurable composition is advantageous in that, unlike other specific types of (meth)acrylate-functionalized monomers, such substances are generally of low to non-sensitivity.

[0063] In yet another aspect of the present invention, the photocurable composition comprises at least one (meth)acrylate-functionalized monomer containing three or more (meth)acrylate functional groups per molecule, particularly the (meth)acrylate of a polyol containing three or more hydroxyl groups per molecule, and their alkoxylated derivatives, such as glycerol, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, triethanolpropane, and polyols that react with 1 to 10 moles of ethylene oxide and / or propylene oxide per mole of the polyol, their ethoxylated and / or propoxylated derivatives. For example, the photocurable composition may contain a total of 0.1 to 20% by mass or 0.5 to 10% by mass of such (meth)acrylate-functionalized monomers (e.g., trimethylolpropane trimethacrylate) containing three or more (meth)acrylate functional groups per molecule.

[0064] Suitable (meth)acrylate-functionalized oligomers include, for example, polyester (meth)acrylates, epoxy (meth)acrylates, polyether (meth)acrylates, urethane (meth)acrylates (also referred to as polyurethane (meth)acrylates or urethane (meth)acrylate oligomers), and combinations thereof, as well as amine-modified and sulfide-modified variants thereof. Some of these (meth)acrylate-functionalized oligomers can function as plasticizers in cured articles obtained by curing the photocurable composition, i.e., their inclusion helps to enhance the flexibility of the cured articles prepared from them.

[0065] Exemplary polyester (meth)acrylates include reaction products of acrylic acid or methacrylic acid or mixtures thereof with hydroxyl-terminated polyester polyols. The reaction process can be carried out such that a significant concentration of residual hydroxyl groups remains in the polyester (meth)acrylate, or all or substantially all of the hydroxyl groups of the polyester polyol can be (meth)acrylated. The polyester polyol can be produced by a polycondensation reaction of a polyhydroxyl-functional component (especially a diol) and a polycarboxylic acid-functional compound (especially a dicarboxylic acid and an anhydride). To prepare the polyester (meth)acrylate, the hydroxyl groups of the polyester polyol are then partially or completely esterified by reacting with (meth)acrylic acid, (meth)acryloyl chloride, (meth)acrylic anhydride, etc. The polyester (meth)acrylate can also be synthesized by reacting a hydroxyl-containing (meth)acrylate such as hydroxyethyl acrylate with a polycarboxylic acid. The polyhydroxyl-functional and polycarboxylic acid-functional components can each have a linear, branched, alicyclic, or aromatic structure and can be used individually or as a mixture.

[0066] Examples of suitable epoxy (meth) acrylates include reaction products of acrylic acid or methacrylic acid or mixtures thereof with glycidyl ethers or esters.

[0067] Exemplary polyether (meth) acrylate oligomers include, but are not limited to, condensation reaction products of acrylic acid or methacrylic acid or mixtures thereof with a polyether polyol which is a polyetherol. Suitable polyetherols can be linear or branched materials containing ether linkages and terminal hydroxyl groups. The polyetherol can be prepared by ring-opening polymerization of an epoxide and other oxygen-containing heterocyclic compounds (e.g., ethylene oxide, 1,2-propylene oxide, butene oxide, tetrahydrofuran and combinations thereof) with a starter molecule. Suitable starter molecules include water, hydroxyl-functional materials, polyester polyols and amines. The polyetherol can also be obtained by condensation of diols such as glycols.

[0068] Urethane (meth) acrylates (also referred to as "polyurethane (meth) acrylates" or "urethane (meth) acrylate oligomers") that can be used in the photocurable composition of the present invention include urethanes based on aliphatic and / or aromatic polyester polyols, polyether polyols and polycarbonate polyols, and aliphatic and / or aromatic polyester diisocyanates and polyether diisocyanates capped with (meth) acrylate end groups.

[0069] In various embodiments, the urethane (meth)acrylate can be prepared by reacting an aliphatic and / or aromatic polyisocyanate (e.g., diisocyanate, triisocyanate) with an OH-group terminated polyester polyol (aromatic, aliphatic, and mixed aliphatic / aromatic polyester polyols), polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethylsiloxane polyol, or polybutadiene polyol, or a combination thereof, and then reacting with a hydroxyl-functionalized (meth)acrylate, such as hydroxyethyl (meth)acrylate or hydroxypropyl (meth)acrylate, to form an isocyanate-functionalized oligomer that provides terminal (meth)acrylate groups. For example, the urethane (meth)acrylate may contain two, three, four or more (meth)acrylate functional groups per molecule. Other orders of addition may also be carried out to prepare the polyurethane (meth)acrylate as known in the art. For example, the hydroxyl-functionalized (meth)acrylate can first be reacted with the polyisocyanate to obtain an isocyanate-functionalized (meth)acrylate, which can then be reacted with an OH-group terminated polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol, polydimethylsiloxane polyol, polybutadiene polyol, or a combination thereof. In yet another embodiment, the polyisocyanate can first react with a polyol containing any of the aforementioned types of polyols to obtain an isocyanate-functionalized polyol, which is then reacted with the hydroxyl-functionalized (meth)acrylate to produce the polyurethane (meth)acrylate. Alternatively, all the components can be combined and reacted simultaneously.

[0070] Any of the above types of oligomers may be modified with an amine or a sulfide (e.g., a thiol) according to procedures known in the art. Such amine- and sulfide-modified oligomers can be prepared, for example, by reacting a relatively small portion (e.g., 2 to 15%) of the (meth)acrylate functional groups present in the base oligomer with an amine (e.g., a secondary amine) or a sulfide (e.g., a thiol), and this modified compound adds to the carbon-carbon double bond of the (meth)acrylate in a Michael addition reaction.

[0071] Exemplary examples of suitable monomeric (meth)acrylate-functionalized organic substances include (meth)acrylated mono- and polyols (polyalcohols) and (meth)acrylated alkoxylated monoalcohols and polyols. The monoalcohols and polyols may be aliphatic (including one or more alicyclic rings) or may contain one or more aromatic rings (such as in the case of phenol or bisphenol A). "Alkoxylated" means that one or more ether moieties (e.g., -CH2CH2-O-) are introduced into one or more hydroxyl groups of the monoalcohol or polyol prior to esterification, such that the base monoalcohol or polyol has reacted with one or more epoxides, such as ethylene oxide, and / or propylene oxide, to introduce one or more (meth)acrylate functional groups. For example, the amount of epoxide reacting with the monoalcohol or polyol may be about 1 to about 30 moles of epoxide per mole of monoalcohol or polyol. Examples of suitable monoalcohols include, but are not limited to, linear, branched, and cyclic C1-C54 monoalcohols (which may be primary, secondary, or tertiary alcohols). For example, the monoalcohol may be a C1-C7 aliphatic monoalcohol. In another embodiment, the monoalcohol may be a C8-C24 aliphatic monoalcohol (e.g., lauryl alcohol, stearyl alcohol). Examples of suitable polyols include organic compounds containing two, three, four or more hydroxyl groups per molecule, such as glycols (diols), such as ethylene glycol, 1,2- or 1,3-propylene glycol, or 1,2-, 1,3- or 1,4-butylene glycol, neopentyl glycol, trimethylolpropane, triethylolpropane, pentaerythritol, glycerol, etc.

[0072] Representative examples of suitable monomeric (meth)acrylate functionalized compounds include, but are not limited to, the following: 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, long chain aliphatic di(meth)acrylate (generally, where R and R' are independently H or methyl and m is an integer from 8 to 24, the formula H2C=CRC(=O)-O-(CH2) m-O-C(=O)CR'=CH2 and the like), alkoxylated (e.g., ethoxylated, propoxylated) hexanediol di(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) neopentyl glycol di(meth)acrylate, dodecyl di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) bisphenol A di(meth)acrylate, ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol diacrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol tetra(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) trimethylolpropane tri(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) glyceryl tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, 2(2-ethoxyethoxy)ethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, alkoxylated lauryl (meth)acrylate, alkoxylated phenol (meth)acrylate, alkoxylated tetrahydrofurfuryl (meth)acrylate, caprolactone (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, dicyclopentadienyl (meth)acrylate, diethylene glycol methyl ether (meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) nonylphenol (meth)acrylate, isobornyl (meth)acrylate, isodecyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, octyldecyl (meth)acrylate (also known as stearyl (meth)acrylate), tetrahydrofurfuryl (meth)acrylate, tridecyl (meth)acrylate, triethylene glycol ethyl ether (meth)acrylate, t-butylcyclohexyl (meth)acrylate, dicyclopentadiene di(meth)acrylate, phenoxyethanol (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, tetradecyl (meth)acrylate, cetyl (meth)acrylate, hexadecyl (meth)acrylate, behenyl (meth)acrylate, diethylene glycol ethyl ether (meth)acrylate, diethylene glycol butyl ether (meth)acrylate, triethylene glycol methyl ether (meth)acrylate, dodecanediol di(meth)acrylate, dipentaerythritol penta / hexa (meth)acrylate, pentaerythritol tetra(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, alkoxylated (e.g., ethoxylated, propoxylated) glyceryl tri(meth)acrylate, and tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, and combinations thereof are included.,

[0073] Other types of polymerizable organic substances containing ethylenically unsaturated functional groups suitable for use in the photocurable composition of the present invention include cyanoacrylate, vinyl ester, 1,1-diester-1-alkene, 1,1-diketo-1-alkene, 1-ester-1-keto-1-alkene, and itaconates containing methylene malonate and / or methylene beta-diketone.

[0074] (The amount of the (meth)acrylate-functionalized oligomer can be varied based on the viscosity of the oligomer or the tensile properties desired for the photocurable composition upon curing. For example, the photocurable composition may contain 1 to 80 or 5 to 60% by mass of the (meth)acrylate-functionalized oligomer based on the total mass of the polymerizable organic substances in the photocurable composition. A suitable (meth)acrylate-functionalized oligomer can be diHEMA trimethylhexyl dicarbamate (UDMA).)

[0075] According to a particularly preferred embodiment of the present invention, the polymerizable organic substances constituting components a) and b) of the photocurable composition are selected to be compatible with the core / shell copolymer also present in the photocurable composition. As used herein, the term "compatible" means that when the components of the photocurable composition are combined, the photocurable composition does not gel or increase in viscosity to an unacceptable extent (i.e., the photocurable composition remains practical, i.e., it can be applied and molded according to the intended end use).

[0076] Photoinitiator The photocurable composition described in this specification contains at least one photoinitiator and is curable by radiation energy (actinic radiation). A photoinitiator can be considered any type of substance that, when exposed to radiation (e.g., actinic radiation), forms species that initiate the reaction and curing of the polymerizable organic substances present in the photocurable composition, such as monomeric polymerizable organic substances and oligomeric polymerizable organic substances. Suitable photoinitiators include both free radical photoinitiators and cationic photoinitiators and combinations thereof. The photoinitiator should be selected to be susceptible to activation by photons of wavelengths associated with actinic radiation intended to cure the photocurable composition. Preferably, the photoinitiator or combination of photoinitiators should be activated at wavelengths of ultraviolet light emitted by lamps commonly or conventionally found in nail salons.

[0077] A free radical polymerization initiator is a substance that forms free radicals when irradiated.

[0078] When the photocurable composition contains a polymerizable organic substance containing a polymerizable (reactive) ethylenically unsaturated functional group such as a (meth) acrylate functional group, the use of a free radical photoinitiator is particularly preferred. Non-limiting types of free radical photoinitiators suitable for use in the photocurable composition of the present invention include, for example, benzoins, benzoin ethers, acetophenones, benzyls, benzyl ketals, anthraquinones, phosphine oxides, α-hydroxy ketones, phenylglyoxylates, α-amino ketones, benzophenones, thioxanthones, xanthones, acridine derivatives, phenazene derivatives, quinoxaline derivatives and triazine compounds. Examples of particularly suitable free radical photoinitiators include, but are not limited to, 2-methylanthraquinone, 2-ethylanthraquinone, 2-chloroanthraquinone, 2-benzyanthraquinone, 2-t-butylanthraquinone, 1,2-benzo-9,10-anthraquinone, benzyl, benzoins, benzoin ethers, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, alpha-methylbenzoin, alpha-phenylbenzoin, Michler's ketone, acetophenone, for example 2,2-dialkoxybenzophenone and 1-hydroxy phenyl ketone, benzophenone, 4,4'-bis-(diethylamino)benzophenone, acetophenone, 2,2-diethyloxyacetophenone, diethyloxyacetophenone, 2-isopropylthioxanthone, thioxanthone, diethylthioxanthone, 1,5-acetonaphthylene, ethyl-p-dimethylaminobenzoate, benzyl ketone, α-hydroxy ket, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzyldimethyl ketal, 2,2-dimethoxy1,2-diphenylethanone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone-1,2-hydroxy-2-methyl-1-phenyl-propanone, oligomeric α-hydroxy ketone, benzoylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl-4-dimethylaminobenzoate, ethyl(2,4,(6 - Trimethylbenzoyl)phenylphosphinate, anisoin, anthraquinone, anthraquinone - 2 - sulfonic acid, sodium salt monohydrate, (benzene)tricarbonylchromium, benzyl, benzoin isobutyl ether, benzophenone / 1 - hydroxycyclohexyl phenyl ketone, 50 / 50 blend, 3,3',4,4' - benzophenone tetracarboxylic dianhydride, 4 - benzoyl biphenyl, 2 - benzyl - 2 - (dimethylamino) - 4' - morpholinobutyrophenone, 4,4' - bis(diethylamino)benzophenone, 4,4' - bis(dimethylamino)benzophenone, camphorquinone, 2 - chlorothioxanthen - 9 - one, dibenzosuberone, 4,4' - dihydroxybenzophenone, 2,2 - dimethoxy - 2 - phenylacetophenone, 4 - (dimethylamino)benzophenone, 4,4' - dimethylbenzyl, 2,5 - dimethylbenzophenone, 3,4 - dimethylbenzophenone, diphenyl(2,4,6 - trimethylbenzoyl)phosphine oxide / 2 - hydroxy - 2 - methylpropiophenone, 50 / 50 blend, 4' - ethoxyacetophenone, 2,4,6 - trimethylbenzoyldiphenylphosphine oxide, phenylbis(2,4,6 - trimethylbenzoyl)phosphine oxide, ferrocene, 3' - hydroxyacetophenone, 4' - hydroxyacetophenone, 3 - hydroxybenzophenone, 4 - hydroxybenzophenone, 1 - hydroxycyclohexyl phenyl ketone, 2 - hydroxy - 2 - methylpropiophenone, 2 - methylbenzophenone, 3 - methylbenzophenone, methyl benzoylformate, 2 - methyl - 4' - (methylthio) - 2 - morpholinopropiophenone, phenanthrenequinone, 4' - phenoxyacetophenone, (cumene)cyclopentadienyliron(II) hexafluorophosphate, 9,10 - diethoxy and 9,10 - dibutoxyanthracene, 2 - ethyl - 9,10 - dimethoxyanthracene, thioxanthen - 9 - one and combinations thereof are included.,

[0079] Suitable cationic photoinitiators include any type of photoinitiator that forms a cation (e.g., a Bronsted acid or a Lewis acid) capable of initiating the reaction of monomeric and (if present) oligomeric polymerizable organic substances in the photocurable composition when exposed to radiation such as actinic radiation. For example, a cationic photoinitiator may be composed of a cationic moiety and an anionic moiety. The cationic moiety of the photoinitiator molecule can be responsible for the absorption of UV irradiation, and the anionic moiety of the molecule becomes a strong acid after UV absorption. Suitable cationic photoinitiators include, for example, onium salts having weakly nucleophilic anions, such as halonium salts, iodonium salts (e.g., diaryliodonium salts such as bis(4-t-butylphenyl)iodonium perfluoro-1-butanesulfonate), or sulfonium salts (e.g., triarylsulfonium salts such as triarylsulfonium hexafluoroantimonate salts), sulfoxonium salts, and diazonium salts. Metallocene salts are another type of suitable cationic photoinitiator.

[0080] The amount of the photoinitiator may be appropriately varied depending on, among other factors, the selected photoinitiator, the amount and type of the polymerizable organic substances (monomeric and oligomeric) present in the photocurable composition, the radiation source, and the radiation conditions used. However, typically, the amount of the photoinitiator can be from 0.05% to 5% by mass, preferably from 0.1% to 2% by mass, based on the total mass of the photocurable composition.

[0081] Other additives / components The photocurable composition of the present invention may optionally contain one or more additives instead of or in addition to the above-described components. Such additives include, but are not limited to, antioxidants / light stabilizers, light blockers / absorbents, polymerization inhibitors, antifoaming agents, fluidizing agents or leveling agents, colorants, pigments, dispersants (wetting agents, surfactants), slip additives, fillers, chain transfer agents, thixotropic agents, rheology modifiers, matting agents, impact resistance improvers (excluding the core / shell copolymer and the oligomeric polymerizable organic substances already described), waxes, or any of various other additives including additives conventionally used in the nail coating field.

[0082] To protect against premature gelling or curing of the photocurable composition, especially in the presence of oxygen or other oxidizing agents, one or more antioxidants may be included in the photocurable composition. Any of the antioxidants known in the art may be used, including, for example, phenol-based antioxidants, phosphorus-based antioxidants, quinone-type antioxidants, and combinations thereof.

[0083] Examples of suitable phenol-based antioxidants include hindered phenol type antioxidants such as hexamethylenebis[(3,5-di-tert-butyl-4-hydroxyphenyl)propionamide], 4,4'-thiobis(6-tert-butyl-m-cresol), 2,2'-methylenebis(4-methyl-5-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), bis[3,3-bis(4-hydroxy-3-tert-butylphenyl)butyric acid] glycol ester, 2,2'-ethylidenebis(4,6-di-tert-butylphenol), 2,2'-ethylidenebis(4-sec-butyl-6-tert-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, bis[2-tert-butyl-4-methyl-6-[2-hydroxy-3-tert-butyl-5-methylbenzyl]phenyl] terephthalate, 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3,5-tris[(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxyethyl] isocyanurate, tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] methane, 2-tert-butyl-4-methyl-6-(2-acryloyloxy-3-tert-butyl-5-methylbenzyl)phenol, 3,9-bis[1,1-dimethyl-2-{(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}ethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, triethylene glycol bis[(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate], and n-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenyl)butane. Butylated hydroxytoluene (BHT) is an example of a preferred antioxidant.

[0084] Examples of suitable phosphorus-based antioxidants include phosphites, phosphonites, etc., such as tris(nonylphenyl) phosphite, tris(2,4-di-tert-butylphenyl) phosphite, tris[2-tert-butyl-4-(3-tert-butyl-4-hydroxy-5-methylphenylthio)-5-methylphenyl] phosphite, tridecyl phosphite, octyldiphenyl phosphite, di(decyl) monophenyl phosphite, di(tridecyl) pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, di(nonylphenyl) pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis(2,4,6-tri-tert-butylphenyl) pentaerythritol diphosphite, tetra(tridecyl) isopropylidene diphenol diphosphite, tetra(tridecyl)-4,4'-n-butylidene bis(2-tert-butyl-5-methylphenol) diphosphite, hexa(tridecyl)-1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl) butane triphosphite, tetrakis(2,4-di-tert-butylphenyl) biphenylene diphosphonite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 2,2'-methylenebis(4-methyl-6-tert-butylphenyl)-2-ethylhexyl phosphite, and 4-[3-[(2,4,8,10-tetra-tert-butyldibenzo[d,f][1,3,2]dioxaphosphepine)-6-yloxy]propyl]-2-methyl-6-tert-butylphenol.

[0085] Quinone-type antioxidants, such as monomethyl ether of hydroquinone (MEHQ), may also be used. Phenothiazine (RTZ) and vitamin E are examples of other suitable antioxidants useful in the present invention.

[0086] Typically, one or more antioxidants can be included in the photocurable composition in a total amount of up to 4% by mass, for example, 0.05 to 2% by mass, based on the mass of the photocurable composition.

[0087] Advantageously, the photocurable composition used in the present invention can be formulated to be solvent-free, i.e., not contain non-reactive volatile substances (substances having a boiling point of 150 °C or lower at atmospheric pressure). For example, the photocurable composition may contain little or no non-reactive solvent relative to the total mass of the photocurable composition, for example, the non-reactive solvent is less than 10% or less than 5% or less than 1% or 0%. In the context of the present invention, "non-reactive" refers to a substance that does not react when exposed to actinic radiation, i.e., a non-polymerizable substance. Such solvent-free or low-solvent compositions can be formulated using various components, such as low-viscosity reactive diluents (monomeric polymerizable organic substances, etc.), which make the photocurable composition have a sufficiently low viscosity even in the absence of a solvent and can be easily applied to the surface of a substrate such as the surface of a target nail at a suitable application temperature.

[0088] However, in other embodiments, the photocurable composition used contains a certain amount of non-reactive solvent, particularly a certain amount of volatile non-reactive solvent (having a boiling point of 150 °C or lower at atmospheric pressure). As an example, when the photocurable composition is formulated for use as a relatively low-viscosity topcoat, basecoat, color coat, or nail polish, one or more non-reactive solvents may be included. For example, the photocurable composition may be composed of at least 0.5 wt%, at least 1 wt%, at least 5 wt%, or at least 10 wt% of non-reactive solvent based on the total mass of the photocurable composition. The photocurable composition can contain 50 wt% or less, 25 wt% or less, or 15 wt% or less of non-reactive solvent based on the total mass of the photocurable composition. Since non-reactive solvents generally reduce the viscosity of the photocurable composition, the amount of non-reactive solvent can be adjusted to achieve the desired viscosity value. Two or more non-reactive solvents may be used in combination. Suitable non-reactive solvents include esters (such as ethyl acetate and butyl acetate), ethers, ketones, glycol ethers, alcohols, hydrocarbons, and combinations thereof.

[0089] In certain embodiments of the present invention, the photocurable composition is liquid at 25 °C. For example, the photocurable composition may be a fluid and / or self-leveling liquid at 25 °C. However, in other embodiments, the photocurable composition may be a gel at 25 °C. Such gels may have no fluidity.

[0090] The viscosity of the photocurable composition at 25 °C can vary widely depending on the intended end use, as discussed in more detail below. For example, the viscosity of the photocurable composition at 25 °C may range from 100 cps to 5,000,000 cps.

[0091] In various embodiments of the present invention (for example, when the photocurable composition is intended for use as a UV gel polish, base coat, color coat, or top coat), the photocurable composition described herein is formulated to have a relatively low viscosity at room temperature or normal temperature. For example, the viscosity of the photocurable composition is selected or adjusted by varying the components present and their relative ratios, and when measured with a Brookfield DV3T Cone and Plate Rheometer using a CPE-52Z cone and a 0.5 mL sample at 25 °C, it can provide a viscosity at 25 °C of 100,000 cps or less, 50,000 cps or less, 25,000 cps or less, or 10,000 cps or less. The viscosity at 25 °C can be, for example, at least 100 cps or at least 500 cps.

[0092] However, in other embodiments of the present invention, the photocurable composition described herein is formulated to have a relatively high viscosity at room temperature or normal temperature. Such a high-viscosity photocurable composition may be of interest when it is intended to be applied to the nail surface and then sculpted (i.e., builder gel, sculpture gel, or nail extension). For example, the viscosity of the photocurable composition is selected or adjusted by varying the components present and their relative ratios, and when measured with a Brookfield DV3T Cone and Plate Rheometer using a CPE-52Z cone and a 0.5 mL sample at 25 °C, it can provide a viscosity at 25 °C of at least 200,000 cps, at least 300,000 cps, or at least 400,000 cps. At the same time, the viscosity should not be so high that it becomes difficult to apply and / or mold the photocurable composition onto the nail surface. The viscosity at 25 °C can be, for example, 5,000,000 cps or less or 4,000,000 cps or less.

[0093] The viscosity and other rheological properties of the photocurable composition can be selected such that when a portion of the photocurable composition is applied to the surface of the nail, it is not easily moved (sculpted) into the desired shape by a nail artist's tool, such as a brush, pusher, and / or spatula. Extruding and sculpting the photocurable composition into the desired shape can be done solvent-free or, at least locally, with the aid of a low-viscosity liquid that reduces the viscosity of the photocurable composition (e.g., a non-reactive solvent and / or a reactive diluent, such as a (meth)acrylate-functionalized monomer). According to an advantageous embodiment of the invention, when the photocurable composition is in solvent-free form or mixed (in limited amounts) with such a liquid, the photocurable composition remains hard (but moldable) and does not flow. An operator, such as a nail artist, can optionally control the viscosity through the application of such a suitable liquid, which can be done only in a selected area of the portion of the photocurable composition on the nail surface until the photocurable composition is cured by exposure to actinic radiation (e.g., UV light).

[0094] In one embodiment, only a single portion of the photocurable composition is applied to an individual nail prior to the photocuring step, although it is also possible in other embodiments of the invention for multiple portions of the photocurable composition to be applied. For example, after applying and shaping a first portion of the photocurable composition, a second portion of a photocurable composition (which may be colored or tinted differently than the first photocurable composition or may otherwise differ in composition) can be applied and shaped, and this second photocurable composition portion is shaped before both portions are photocured to provide a cured nail coating.

[0095] Formulation of the photocurable composition The relative mass ratios of component (a) (at least one (meth)acrylate-functionalized monomer), component (b) (at least one (meth)acrylate-functionalized oligomer), component (c) (at least one core / shell copolymer particle), and component (d) (at least one photoinitiator) are not considered particularly important and can be varied as desired based on the characteristics required for the specific components, the photocurable composition, and the cured article obtained therefrom. For example, the photocurable composition in a particular embodiment may contain 5 to 45% by mass of component (a), 5 to 60% by mass of component (b), 10 to 60% by mass of component (c), and 0.1 to 10% by mass of component (d), and the masses of (a), (b), (c), and (d) are equal to 100% in total (this means that the respective mass% ranges of (a), (b), (c), and (d) above are based on the combined mass of these components, not the total mass of the photocurable composition which may contain components other than (a), (b), (c), and (d)).

[0096] According to a preferred embodiment, the components of the photocurable composition are selected such that the photocurable composition is liquid in a temperature range of at least 0 °C to 60 °C. As used in this context, the term "liquid" does not exclude the possibility that portions of the photocurable composition (especially the core / shell copolymer) are present in the form of small, well-dispersed particles within a matrix that is normally liquid.

[0097] Generally speaking, the photocurable composition according to the present invention can be prepared by combining the individual components. When a (meth)acrylic polymer is a component of the photocurable composition, the core / shell copolymer and the (meth)acrylic polymer may be supplied to the photocurable composition separately or, for example, together as part of a polymer composition obtained via a core / shell copolymerization process in which the (meth)acrylic polymer is prepared as one of those steps. The photocurable composition may also be prepared first as a masterbatch composed of a core / shell copolymer, a (meth)acrylic polymer, and a relatively small amount of a polymerizable organic substance, and later combined with additional polymerizable organic substances and optionally other components (such as photoinitiators, etc.) to produce the final photocurable composition used for producing a cured nail coating using the masterbatch method.

[0098] Use of the photocurable composition in nail coating formation The photocurable composition utilized in the present invention is photocured (i.e., cured by exposure to light, particularly actinic radiation such as visible light or UV light, etc.). However, such photocuring is not carried out until the photocurable composition is applied to the surface of the nail and, in certain embodiments, shaped into the desired form. For example, a method for forming a cosmetic nail coating includes the steps of disposing the above-described photocurable composition on the nail of interest, optionally shaping the photocurable composition, and exposing the photocurable composition to UV light.

[0099] The placement of a portion (such as beads, etc.) of the photocurable composition may be carried out directly by an operator (which may be a nail technician or an individual whose nails are being coated) squeezing from a tube container or extruding onto the nail or an application tool from a syringe with a plunger. Alternatively, the application of the photocurable composition may be completed with the aid of an application tool such as an acrylic brush or a gel brush, a pusher and / or a spatula, or other such tools conventionally used for applying nail coating products.

[0100] After placing beads of the photopolymerizable composition on the nail, the operator can manipulate the photocurable composition to move it to a desired position and form it into a desired shape, with or without the use of a nail form. Also, a nail mold can be used, a portion of the photocurable composition (preferably in the form of a high-viscosity liquid or gel) is applied to the surface of the nail mold, the portion to which the photocurable composition is applied is shaped within the nail mold, and the nail mold containing the shaped portion of the photocurable composition is applied to the nail of interest (bringing the surface having the shaped portion of the photocurable composition into contact with the surface of the nail), the photocurable composition is cured by exposure to actinic radiation, providing a cured nail coating, and thereafter, the nail mold is separated from the cured nail coating.

[0101] After the photocurable composition is applied to the surface of the nail and optionally shaped or formed, the nail on which the photocurable composition is disposed is exposed to actinic radiation such as UV light under conditions effective to cure the photocurable composition. A suitable source of UV light may generally be a UV lamp such as those used in nail salons. Such UV lamps can operate at any wavelength necessary to cure the photocurable composition, such as between 320 nm and 420 nm. The exposure time should be of sufficient length to achieve curing of the photocurable composition. For example, this can be from 5 seconds to 6 minutes.

[0102] The term "UV lamp" is meant to be interpreted broadly. This refers to any source of electromagnetic radiation that has sufficient intensity to cure the photocurable composition used in the present invention and exhibits light in the range of 320 nm to 420 nm. The term "UV lamp" includes conventional UV lamps such as compact fluorescent lamps that emit UV light in the above range. The term "UV lamp" also refers to new light sources or UV irradiation such as light-emitting diode lamps (commonly referred to as "LED lamps") that emit electromagnetic radiation containing UV light in the range of 320 nm to 420 nm with sufficient intensity to cure the photocurable composition. The term "UV lamp" also refers to any other kind of light source that has sufficient intensity to cure the photocurable composition and contains UV light in the range of 320 nm to 420 nm.

[0103] Following the curing step, the cured nail coating can be subjected to one or more further procedures such as trimming, sanding, buffing, polishing, decoration, etc. It is also possible to form multiple layers of the photocurable coating on the surface of the nail by applying a first layer of the photocurable composition to the surface of the nail, optionally shaping and curing it, and then applying at least one further layer of the photocurable composition on top of the first cured layer and optionally shaping and curing it.

[0104] Packaging article containing a photocurable composition The above-described photocurable composition is packaged in a suitable container and can be stored and / or transported before being used to form a cured nail coating. Thus, the packaged article can include the container and the photocurable composition disposed within the container, and the packaged article has a dispensing component that can dispense the photocurable composition from the container. Suitable types of containers include tubes, bottles (including wide-mouth bottles or pots), and syringes (equipped with a plunger). The container can be rigid or flexible; for example, the container can be a flexible tube or bottle that allows the user to squeeze the container to facilitate dispensing of the photocurable composition through an aperture in the container. The container can be provided with a releasable seal such as a screw cap, press-on cap, or flap that can be sealed to protect the contents of the container when not in use or to seal against accidental release. Such a releasable seal can include an application tool such as a brush. To enhance the storage stability of the photocurable composition contained in the container, the container is generally preferably opaque. The dispensing component can be, for example, a brush, foam applicator, wick, nozzle, roller, needle, or aperture (orifice), etc. As an example, the dispensing component is an aperture configured to directly deliver a desired portion of the photocurable composition, such as beads, directly to the nail surface or to an applicator (coating tool), such as a brush, pusher, or spatula, that is later used to transfer the portion of the photocurable composition to the nail surface.

[0105] Also contemplated by the present invention is a kit comprising a packaged article including a container and a photocurable composition disposed within the container, at least one application tool, and instructions for dispensing, applying, and curing the photocurable composition to provide a nail coating. The packaged article can have a dispensing component as described previously. The instructions can be provided in the form of an instruction sheet and / or printed on the packaging container containing the components of the kit.

[0106] Aspects of the Invention Certain illustrative and non-limiting aspects of the present invention can be summarized as follows.

[0107] Aspect 1: A nail coating, wherein the coating is a photocured product of a photocurable composition, and the photocurable composition comprises a) at least one (meth)acrylate-functionalized monomer, and b) at least one (meth)acrylate-functionalized oligomer, and c) particles of at least one core / shell copolymer, and d) at least one photoinitiator A nail coating containing the above.

[0108] Aspect 2: The coating according to Aspect 1, wherein the core / shell copolymer is composed of a core containing an elastomeric polymer having a glass transition temperature below 0 °C and at least one shell containing a non-elastomeric polymer having a glass transition temperature of at least 30 °C.

[0109] Aspect 3: The coating according to Aspect 1 or 2, wherein the particles of at least one core / shell copolymer are suspended in a liquid matrix composed of a) and b).

[0110] Aspect 4: The coating according to any one of Aspects 1 to 3, wherein the particles of at least one core / shell copolymer have an average particle size of 25 to 900 nm.

[0111] Aspect 5: The coating according to any one of Aspects 1 to 4, wherein the photocurable composition is composed of at least one non-reactive solvent in a total amount of 0 to 20% by mass based on the mass of the photocurable composition.

[0112] Aspect 6: The coating according to any one of Aspects 1 to 5, wherein the photocurable composition is composed of particles of at least one core / shell copolymer in an amount of 1 to 60% by mass, 5 to 55% by mass, or 10 to 50% by mass based on the total mass of the photocurable composition.

[0113] Aspect 7: The coating according to any one of Aspects 1 to 6, wherein at least one shell contains, in polymerized form, at least one monomer selected from the group consisting of alkyl methacrylates having a C1-C12 alkyl chain, C6-C12 vinyl aromatic organic compounds, acrylonitrile, and combinations thereof, and the shell may be crosslinked.

[0114] Aspect 8: The coating according to any one of Aspects 1 to 7, wherein at least one shell contains, in polymerized form, methyl methacrylate, and the shell may be crosslinked.

[0115] Aspect 9: The coating according to any one of Aspects 1 to 8, wherein the core contains, in polymerized form, at least one monomer selected from the group consisting of C4-C12 conjugated dienes and C1-C12 alkyl acrylates.

[0116] Aspect 10: The core / shell copolymer is a) a core / shell copolymer comprising a core composed of polymerized butyl acrylate and a shell composed of polymerized methyl methacrylate, and b) a core / shell copolymer comprising a core composed of copolymerized styrene and butadiene and a shell composed of polymerized methyl methacrylate The coating according to any one of Aspects 1 to 9, selected from the group consisting of.

[0117] Aspect 11: The coating according to any one of Aspects 1 to 10, wherein the core is 60% to 95% by mass of the total mass of the core / shell copolymer.

[0118] Aspect 12: The coating according to any one of Aspects 1 to 11, wherein at least one (meth)acrylate-functionalized monomer contains at least one monomer selected from the group consisting of hydroxyethyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, polyethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

[0119] Aspect 13: The coating according to any one of Aspects 1 to 12, wherein at least one (meth)acrylate-functionalized oligomer comprises at least one (meth)acrylate-functionalized urethane oligomer.

[0120] Aspect 14: The coating according to any one of Aspects 1 to 13, wherein at least one or more photoinitiators are present in a total amount of 0.1% to 5% based on the total mass of the photocurable composition.

[0121] Aspect 15: The coating according to any one of Aspects 1 to 14, wherein the photocurable composition has a viscosity of 100 to 5,000,000 cps at 25°C.

[0122] Aspect 16: The coating according to any one of Aspects 1 to 15, wherein the photocurable composition is further composed of at least one (meth)acrylic polymer that is not a core / shell copolymer.

[0123] Aspect 17: The coating according to any one of Aspects 1 to 16, having an impact strength of at least 15 J / m to at least 20 J / m at 25°C as measured by energy loss per unit area.

[0124] Aspect 18: The coating according to any one of Aspects 1 to 17, wherein the nail is a human fingernail or toenail.

[0125] Aspect 19: a) a step of disposing a photocurable composition on the surface of the nail; b) a step of exposing the photocurable composition to ultraviolet light or visible light and a method for forming a coating on a nail, comprising: A method, wherein the photocurable composition comprises at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, particles of at least one core / shell copolymer, and at least one photoinitiator, or is identical to the photocurable composition according to any one of aspects 1 to 18.

[0126] Aspect 20: The method according to aspect 19, wherein the photocurable composition is disposed on the surface of the nail and formed into a continuous layer before being photocured.

[0127] Aspect 21: A packaged article comprising a container and a photocurable composition disposed within the container, the packaged article having a dispensing component capable of dispensing the photocurable composition from the container, the photocurable composition comprising at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, particles of at least one core / shell copolymer, and at least one photoinitiator, or being identical to the photocurable composition according to any one of aspects 1 to 18.

[0128] Aspect 22: The packaged article according to aspect 21, wherein the container is a tube, a bottle or a syringe.

[0129] Aspect 23: The packaged article according to aspect 21 or 22, wherein the dispensing component is a brush, a foam applicator, a wick, a nozzle, a roller, a needle or an aperture.

[0130] Aspect 24: A kit comprising a packaged article comprising a container and a photocurable composition disposed within the container, at least one application instrument, and instructions for use for dispensing, applying and curing the photocurable composition to provide a nail coating, the photocurable composition comprising at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, particles of at least one core / shell copolymer, and at least one photoinitiator, or being identical to the photocurable composition according to any one of aspects 1 to 18.

[0131] Aspect 25: The kit according to aspect 24, wherein at least one of the application devices comprises at least one of a brush, a pusher, or a spatula.

[0132] In this specification, embodiments are described in a way that enables writing a clear and concise specification, but it is intended and understood that the embodiments can be variously combined or separated without departing from the invention. For example, it will be understood that all the preferred features described herein are applicable to all aspects of the invention described herein.

[0133] In some embodiments, the invention herein can be construed as excluding any element or method step that does not significantly affect the basic and novel features of the invention. Further, in some embodiments, the invention can be construed as excluding any element or method step not specified herein.

[0134] The invention is illustrated and described herein with reference to specific embodiments, but the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims without departing from the invention.

Examples

[0135] Using the components listed in Table 1, two base photocurable compositions (Base Formulations 1 and 2) were prepared. The amounts listed are parts by mass. All components (except the urethane oligomer) were added to a 4-ounce amber wide-mouth glass bottle and then mixed with a roller at 60 °C for 30 minutes. Then the urethane oligomer was added to the wide-mouth bottle and the formulation was further mixed with a roller at 60 °C for an additional 1.5 hours to obtain a clear viscous solution.

[0136]

Table 1

[0137] Six different polymer powders were blended at various ratios into each of base formulations 1 and 2 (10 - 40% by mass relative to the total mass of the base formulation + polymer powder).

[0138] The polymer powders used were as described in Table 2. Plastistrength®, Durastrength®, and Clearstrength® are all registered trademarks of Arkema.

[0139]

Table 2

[0140] The curable compositions were prepared from the base formulations and polymer powders according to the following procedure. 20 g of either base formulation 1 or base formulation 2 was added to a Flacktek® high speed mixer cup. 5 grams of the designated polymer powder was added and the mixture was mixed at high speed for 4 minutes at 3000 RPM. In some cases, a slightly turbid low viscosity liquid was obtained, and in other cases, a slightly turbid high viscosity gel was obtained. The difference in consistency depends on the amount of monomer and oligomer and / or the amount and type of core / shell particles.

[0141] The viscosity of each of the obtained photocurable compositions was measured using a Brookfield DV3T Cone and Plate Rheometer. All measurements were performed at 25 °C with a 0.5 mL sample using a CPE - 52Z cone. The shear rate was measured and the data was collected and analyzed using Rheocalc software. The measured viscosities are reported in Table 3. For comparison, it is known that a commercially available acrylic nail builder / sculpture gel product has a viscosity of 2,500,000 cps.

[0142]

Table 3

[0143] The impact test on the photocurable composition was carried out according to the following procedure. Three samples of each photocurable composition were warmed in an oven at 60 °C, applied to a silicone mold, and cured using a Phoseon LED curing lamp at 395 nm and 30 fpm. The obtained cured bricks were notched and their impact strength was measured after equilibration overnight at 50% RH. The impact strength of the bricks was measured using a Zwick / Roell HIT5.5P Izod impact tester. The results obtained are shown in Table 4. When using a high molecular weight polymer powder containing an acrylic copolymer (Polymer A), the impact strength is very low (8.8 J / m). However, a photocurable composition containing a core / shell acrylic impact modifier with a rubbery core (Durastrength® 440) shows an increase in impact strength of 2 to 3 times that of the cured product (19.6 and 28.7 J / m depending on the base formulation). The difference between Durastrength® 350 and Durastrength® 440 is the size of the rubbery core. The impact strength achieved using Durastrength® 440 is higher than that observed using Durastrength® 350. Photocurable compositions containing Clearstrength® XT-100 in both base formulations have impact strengths of 29.8 J / m and 39.3 J / m respectively when cured. For comparison, it has been found that a commercially available acrylic nail builder / sculpture gel product has an average energy loss per area of 12.7 J / m when cured and tested in the same way.

[0144]

Table 4

Claims

Claim 1 A coating for nails, wherein the coating is a photocured product of a photocurable composition, and the photocurable composition comprises a) at least one (meth)acrylate-functionalized monomer, b) at least one (meth)acrylate-functionalized oligomer, c) particles of at least one core / shell copolymer, d) at least one photoinitiator and is a coating for nails. Claim 2 The coating according to claim 1, wherein the core / shell copolymer is composed of a core containing an elastomeric polymer having a glass transition temperature of less than 0 °C and at least one shell containing a non-elastomeric polymer having a glass transition temperature of at least 30 °C. Claim 3 The coating according to claim 1 or 2, wherein the particles of the at least one core / shell copolymer are suspended in a liquid matrix composed of a) and b). Claim 4 The coating according to any one of claims 1 to 3, wherein the particles of the at least one core / shell copolymer have an average particle size of 25 to 900 nm. Claim 5 The coating according to any one of claims 1 to 4, wherein the photocurable composition is composed of at least one non-reactive solvent in a total amount of 0 to 20% by mass based on the mass of the photocurable composition. Claim 6 The coating according to any one of claims 1 to 5, wherein the photocurable composition is composed of the particles of the at least one core / shell copolymer in an amount of 1 to 60% by mass, 5 to 55% by mass, or 10 to 50% by mass based on the total mass of the photocurable composition. Claim 7 The coating according to any one of claims 1 to 6, wherein the at least one shell, in polymerized form, contains at least one monomer selected from the group consisting of alkyl methacrylates having a C1-C12 alkyl chain, C6-C12 vinyl aromatic organic compounds, acrylonitrile, and combinations thereof, and the shell may be crosslinked. Claim 8 The coating according to any one of claims 1 to 7, wherein the at least one shell, in polymerized form, contains methyl methacrylate, and the shell may be crosslinked. Claim 9 The coating according to any one of claims 1 to 8, wherein the core contains at least one monomer selected from the group consisting of C4-C12 conjugated dienes and C1-C12 alkyl acrylates in a polymerized form.

10. The core / shell copolymer is a) a core / shell copolymer comprising a core composed of polymerized butyl acrylate and a shell composed of polymerized methyl methacrylate, and b) a core / shell copolymer comprising a core composed of copolymerized styrene and butadiene and a shell composed of polymerized methyl methacrylate The coating according to any one of claims 1 to 9, which is selected from the group consisting of

11. The coating according to any one of claims 1 to 10, wherein the core is 60% by mass to 95% by mass of the total mass of the core / shell copolymer.

12. The coating according to any one of claims 1 to 11, wherein the at least one (meth)acrylate-functionalized monomer contains at least one monomer selected from the group consisting of hydroxyethyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, polyethylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

13. The coating according to any one of claims 1 to 12, wherein the at least one (meth)acrylate-functionalized oligomer contains at least one (meth)acrylate-functionalized urethane oligomer.

14. The coating according to any one of claims 1 to 13, wherein the at least one or more photoinitiators are present in a total amount of 0.1% to 5% based on the total mass of the photocurable composition.

15. The coating according to any one of claims 1 to 14, wherein the photocurable composition has a viscosity of 100 to 5,000,000 cps at 25°C.

16. The coating according to any one of claims 1 to 15, wherein the photocurable composition is further composed of at least one (meth)acrylic polymer that is not a core / shell copolymer.

17. The coating according to any one of claims 1 to 16, having an impact strength of at least 15 J / m at 25°C as measured by energy loss per area.

18. The coating according to any one of claims 1 to 17, wherein the nail is a human fingernail or toenail.

19. a) a step of disposing a photocurable composition on the surface of the nail; b) a method of forming a coating on the nail, comprising a step of exposing the photocurable composition to ultraviolet light or visible light wherein the photocurable composition comprises at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, at least one core / shell copolymer particle, and at least one photoinitiator.

20. The method according to claim 19, wherein the photocurable composition is disposed on the surface of the nail and formed into a continuous layer before being photocured.

21. A packaged article comprising a container and a photocurable composition disposed in the container, the packaged article having a dispensing component capable of dispensing the photocurable composition from the container, the photocurable composition comprising at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, at least one core / shell copolymer particle, and at least one photoinitiator.

22. The packaged article according to claim 21, wherein the container is a tube, a bottle or a syringe.

23. The packaged article according to claim 21 or 22, wherein the dispensing component is a brush, a foam applicator, a wick, a nozzle, a roller, a needle or an aperture.

24. A kit comprising a packaged article comprising a container and a photocurable composition disposed in the container, at least one applicator, and instructions for use for dispensing, applying, and curing the photocurable composition to provide a nail coating, the photocurable composition comprising at least one (meth)acrylate-functionalized monomer, at least one (meth)acrylate-functionalized oligomer, at least one core / shell copolymer particle, and at least one photoinitiator.

25. The kit according to claim 24, wherein the at least one applicator comprises at least one of a brush, a pusher, or a spatula. ​

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