KR100475224B1 - Monomer useful in the formulation of radiation curable coatable compositions and method for applying such compositions - Google Patents

Abstract

The present invention comprises (a) a polyfunctional isocyanurate containing (b) hydroxyalkyl acrylate and (c) at least three terminal reactors reacted with tertiary amine alcohols, wherein the molar ratio of a: b: c is About 1: 1 to 2.5: 0.5 to 2, b + c of at least 3, and providing a monomer not greater than the total number of terminal reactors of (a), which monomer is useful for preparing a radiation curable coating composition Do. This monomer is used in radiation curable coating compositions useful as floor finishing materials and floor finishing systems comprising the coating compositions and primers described above. The invention also describes a method of treating a substrate using a floor finishing system.

Description

      MONOMER USEFUL IN THE FORMULATION OF RADIATION CURABLE COATABLE COMPOSITIONS AND METHOD FOR APPLYING SUCH COMPOSITIONS

The present invention provides a radiation curable coating composition useful as a floor finishing material, a floor finishing system using the composition, a method of applying a protective coating to a particular substrate, a substrate coated with the composition, and a prolific product useful for producing the radiation curable coating composition. Soluble isocyanate monomers.

Polymeric compositions are used in the formulation of various coating compositions such as, for example, floor finishes. Commercially available floor finishing compositions are generally aqueous emulsion-based polymer compositions comprising at least one organic solvent, plasticizer, coating aid, antifoaming agent, polymer emulsion, wax, and the like. Typically, these compositions have a relatively low solids content (eg, about 15% to about 35%). The application of the polymer composition to the bottom surface, followed by drying in air, usually at ambient temperature and ambient humidity, results in one film, which acts as a protective barrier against soil deposited on the floor by, for example, human trafficking. do. While many commercial floor finishes have been commercially available and at least some have achieved commercial success, these commercial finishes are not 100% satisfactory for several reasons. For example, when a conventional floor finishing composition is applied to the floor surface, several coating coatings are generally required to obtain a suitable finish appearance. Each composition applied in succession must be dried before additional coating is applied and / or before pedestrians pass through the treated floor. The composition is dried in air at ambient temperature and ambient humidity, the drying time of which depends on the flow of air on the floor as well as the relative humidity of the air. Conventional floor finishes weaken when exposed to water for short periods of time or when exposed to strong chemical cleaners such as during cleaning. Moreover, these finishes need to be maintained almost daily (eg buffing) to provide a consistent and desirable appearance.

In view of the foregoing, it can be applied in a single application and can be immediately dried and cured in air, resulting in low maintenance costs, durable, water and chemical resistance, and labor intensive (eg daily) to provide a lasting and desirable appearance. It is desirable to provide a floor finishing composition that can provide a finish that requires no maintenance. It is also desirable to provide such low cost, durable, water and chemical resistant finishes in a form that can be easily removed from the surface to which it is applied, for example a floor comprising conventional vinyl floor tiles.

It is known that irradiating ethylenically unsaturated compounds in the presence of a photoinitiator induces a photopolymerization reaction. The term "photoinitiator" as used herein refers to any material or any combination thereof that forms free radicals that can interact with light to induce free radical polymerization reactions. When radicals are produced by irradiating a free radical polymerizable reaction system with ultraviolet ("UV") and / or visible light, photochemical polymerization or photoinitiated free radical polymerization occurs. When energy is absorbed by one or more compounds in the system, the excited species are formed, and then the excited species decompose into radicals, or the excited species and the second compound interact with the first excited compound. To form radicals derived from both of the second compounds. It is recognized that the exact mechanism for the photoinitiation reaction may not be as obvious and may involve any or all of the aforementioned pathways.

Photochemical polymerization can be used to manufacture decorative and / or protective coatings and inks for metals, paper, wood and plastics, as well as for the cure of lithography and dental materials for the manufacture of integrated and printed circuits. come. Many of the known uses involve photopolymerization and crosslinking together, which is typically accomplished by using ethylenically polyunsaturated monomers. As well as acrylate-based systems, systems based on unsaturated polyesters and styrenes are also common.

UV curable protective finishes have also been applied to vinyl “wax-free” flooring during the sheet manufacturing process to provide gloss as well as wear resistance. These protective finishes are generally not easily stripped from the floor to which they are applied using conventional stripping methods (eg, applying a chemical stripping composition using a stripping pad or brush). In addition, curing of these finishes is typically performed using strong intensity light. Lamps require higher power requirements, more power supply and generally require conduit exhaust to remove ozone. Often these finishes are cured in an inert atmosphere to prevent the oxygen detrimental effects on the curing process. Due to the aforementioned power requirements and the like, the use of UV curable polymer systems for floor treatment has generally been limited to factory scale processes where the costs and additional burdens associated with these systems are more easily tolerated.

Other problems have emerged in the manufacture of UV curable systems for existing floors (eg floors already installed in a building). In the use of any type of finish for an existing floor, a cured floor finish is generally preferred in that it does not change the color of the floor. To achieve this goal, the finish should be transparent and contain little visible color. This is especially necessary to maintain floors made of white floor tiles where the color of the hardened finish is noticeably noticeable when the floor color changes. In addition, in order to make the floor finishing composition suitable for the art, the applied floor finish should also be less odor before curing.

For example, certain resins containing functional polymerizable vinyl groups (e.g., acrylates or vinylethers / maleates containing amines or thiols) are subject to free radical polymerization when exposed to UV or visible light in the presence of photoinitiators. It is known that it can superpose | polymerize in air. Although these resins can be used to provide coatings with toughness and wear resistance, the coatings usually have a color ranging from yellow to dark orange or have an unpleasant odor before curing. As a result, these resins are considered unsuitable for use as floor finishing materials.

As mentioned above, oxygen in the atmosphere is known to inhibit photoinitiated polymerization reactions to reduce or prevent hardening of the coating surface, or to provide coatings with poor surface properties. Various processing techniques have been proposed for removing the oxygen effect from the reacting resin. One of them is to separate the coating from the chamber and purge the chamber with an inert gas (eg nitrogen) to proceed the polymerization reaction in an environment with little oxygen. Another method is to initiate the polymerization reaction using strong UV radiation with a large amount of photoinitiator in the uncured resin. None of these proposed techniques is practical for floor finishing systems for use on already installed floors. Smaller, lighter, cheaper, low intensity light sources that can operate on cells or on 110 volt, 15 amp circuits are preferred, but known UV curable polymer systems have a lower curing rate when using low intensity light rays. It is lowered and the hardening inhibition rate is larger.

There has long been a need for coating compositions that can be easily applied to substrates, for example floors already installed and suitable for use as floor finishes that can be cured in air when exposed to low intensity radiation such as ultraviolet light. . Such coating compositions, preferably coating compositions that do not have an unpleasant odor, are desired to be provided in a form that can easily be applied to the floor and provide a protective coating having a color that is almost invisible upon subsequent curing. It is also desirable to provide the protective coatings described above in a form that can be removed from the floor as needed (eg with a suitable chemical stripping agent).

Summary of the Invention

The present invention provides a coating composition that can be cured rapidly in air by low intensity radiation exposure to provide a durable protective coating for a suitable substrate such as vinyl floor tiles. The resulting coating requires little maintenance and can be easily and quickly stripped from the substrate by using a suitable stripping composition as described above.

The present invention also provides a radiation curable coating composition comprising (a) a polyfunctional isocyanurate containing (b) hydroxyalkyl acrylate and (c) at least three terminal reactors reacted with a tertiary amine alcohol. Wherein the molar ratio of a: b: c is about 1: 1 to 2.5: 0.5 to 2, b + c is at least 3, and the total number of terminal reactors of (a) is provided. Not greater than

Preferred monomers include compounds of formula (I)

In the above formula,

R ₁ and R ₂ are H or CH ₃ ,

R ₃ and R ₄ may each be an alkyl group having 1 to 12 carbon atoms (straight, branched or cyclic) or

R ³ and R ⁴ together may form a divalent cycloalkanediyl, oxacycloalkanediyl or azacycloalkanediyl linking group having from 2 to 12 carbon atoms,

Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ and Z ₆ are each a divalent group having 1 to 18 carbon atoms, preferably an alkanediyl group having 1 to 18 carbon atoms (straight, branched or Cyclic), most preferably a straight alkanediyl group having 1 to 4 carbon atoms.

The aforementioned monomers are formulated into the radiation curable coating composition as the first monomer together with the second monomer and the photoinitiator. The first monomer preferably comprises the reaction product of a trimer of hexane diisocyanate (optionally mixed with allophanate of hexane diisocyanate), hydroxyalkyl acrylate and tertiary amine alcohol. The first monomer is typically present in the composition in an amount of about 10% to about 80% by weight. The second monomer can be selected from a variety of optional polymerizable monomers. It is preferable that a 2nd monomer is an acrylate as further demonstrated below. Typically, the second monomer is present in the composition in an amount of about 5% to about 90% by weight. The composition may further comprise additional polymerizable monomers, including combinations of two or more of the monomers, in addition to the second monomer. The composition includes a suitable photoinitiator to promote curing by UV radiation. Initiators suitable for making transparent coatings containing small amounts of visible color are preferred. The photoinitiator concentration in the composition may vary depending on the nature of the other components of the composition and the nature of the photoinitiator. Concentrations of photoinitiators are commonly from about 2% to about 10% by weight.

As mentioned above, certain terms are used in a specific meaning. "Ultraviolet radiation" and "UV radiation" are used interchangeably to refer to a spectrum of light rays that include a wavelength in the range from about 180 nm to about 400 nm. The term "coating composition" means a liquid composition that can be applied to a substrate and then solidified (eg, by UV curing) to form a cured coating on the substrate. The term "radiation curable" referring to the coating composition means that the coating composition forms a cured coating upon exposure to radiation such as UV radiation or visible light (eg, 180 to 800 nm). The term "substrate" refers to any surface to which the coating composition of the present invention is applied, which, unless otherwise specified, includes vinyl floor tiles (e.g., tiles already covered with floor sealants, etc.), ceramic tiles, wood, marble And the like. The term "acrylate" as used herein is to be interpreted to include acrylate and methacrylate species. The term "monomer" refers to any chemical species that contains one or more free radically polymerizable groups (eg, acrylates, methacrylates). The term "tertiary amine alcohol" refers to a tertiary amine containing an alcohol functional group.

The present invention also provides a system for floor finishing comprising the radiation curable coating composition described above and a primer composition that can be coated onto a substrate. As one aspect of the invention the coating composition has already been described above. The primer preferably comprises acrylated latex having a solids content of about 2% to about 40% by weight in water. The latex is applied to a substrate and dried before applying the coating composition. The primer is provided in one layer on the substrate to which the coating composition can bind. In addition, the cured coating composition is easily stripped from the substrate in the presence of a latex primer.

The present invention also provides a method of applying a protective coating to a substrate comprising the following steps (A) and (B):

(A) a polyfunctional isocyanurate containing (i) at least three terminal reactors reacted with (b) hydroxyalkyl acrylate and (c) tertiary amine alcohol, wherein a: b: the molar ratio of c is about 1: 1 to 2.5: 0.5 to 2, b + c is at least 3 and is not greater than the total number of terminal reactors of (a),

(ii) a second monomer, and

(iii) photoinitiators

Applying a radiation curable coating composition to the substrate, and

(B) curing the composition by ultraviolet exposure to form a protective coating on the substrate.

In one aspect of the invention, the first monomer, the second monomer and the photoinitiator have already been described above. In total, the coating composition preferably contains at least about 90% solids (eg, up to about 10% solvent). The composition curing process of step (B) can be carried out in air at normal temperature and humidity (eg ambient conditions). Although high intensity radiation is generally preferred for faster curing of the coating composition and to perform curing step (B), the coating composition can also be cured with low intensity UV radiation. Curing the coating composition at low UV intensity is considerably fast using a low intensity radiation light source that provides at least one band having a wavelength of about 300 nm or less and one second band having a wavelength of about 300 nm to about 400 nm. (For example, 30 seconds or less). In order to cure (typically about 0.03 mm thick) the coating within a time of about 30 seconds or less, the low intensity radiation source may have a first band with a center wavelength around 254 nm and a center wavelength between 350 and 370 nm (eg, Emitting a second band of about 365 nm). As a low intensity radiation light source, a light source providing a radiation intensity of about 5 mW / cm 2 to about 15 mW / cm 2 is suitable. It is desirable to expose the coating to low intensity radiation for a time of up to about 30 seconds.

In addition, the method may include applying a primer composition to the bottom and drying the primer composition before the application step (A) described above to form a primer coating on the substrate. As described above, preferred primer compositions are acrylated latexes, preferably having a solids content of about 2% to about 40% by weight.

The present invention also provides a coating made of the radiation curable coating composition described above. The present invention also provides a substrate coated with this coating.

The present invention also provides a method of applying a protective coating to a substrate, comprising the following steps (a) to (d):

(a) applying a coating acrylated latex primer composition to a substrate,

(b) drying the primer composition to form an acrylated polymer primer coating on the substrate,

(c) applying a radiation curable coating composition to the primer coating, and

(d) exposing the radiation curable coating composition to ultraviolet light to cure the composition to form a protective coating on the substrate.

The details of the invention will be fully appreciated by those skilled in the art in view of the remainder of the description, including the description of the preferred embodiments and the claims.

Detailed Description of the Preferred Embodiments

Next, a preferred embodiment of the present invention has been described. Preferred embodiments are for illustrating the present invention, whereby the scope of the present invention is not unduly limited.

The coating composition of the present invention is blended with a first monomer comprising isocyanurate. The first monomer is preferably derived from the reaction of polyfunctional isocyanates, hydroxyalkyl acrylates and tertiary amine alcohols. In addition, the composition of the present invention comprises a second monomer and a photoinitiator.

The individual components used in the formulation of the coating composition are described below.

First monomer

In the formulation of a radiation curable coating composition that can be used as a floor finish, the final product (e.g., the final cured coating) has little visible color, provides a harder and more durable finish, and the composition is applied It is preferred that it can be easily removed from the substrate. To this end, it has been found that compositions comprising a particular class of multifunctional isocyanurates provide the desired coatings.

The first monomer is preferably prepared from the reaction of polyfunctional isocyanurate, (hydroxyalkyl) dialkylamine and hydroxyalkyl acrylate. In the reaction, about 1 mole of multifunctional isocyanurate is reacted with about 1 mole to about 2.5 moles of hydroxyalkyl acrylate and about 0.5 mole to about 2.0 moles of tertiary amine alcohol. According to this preparation, the first monomer contains (a) a polyfunctional isocyanurate containing at least three terminal reactors reacted with (b) hydroxyalkyl acrylate and (c) tertiary amine alcohol. and the molar ratio of a: b: c is about 1: 1 to 2.5: 0.5 to 2, b + c is at least 3 and is not greater than the total number of terminal reactors of (a). The terminal reactor of the polyfunctional isocyanurate comprises isocyanate groups (-NCOs), each of which reacts with the hydroxyl groups of both hydroxyalkyl acrylate and tertiary amine to form a urethane linkage (-NH- CO-O-) can be formed. Theoretical functional groups of the multifunctional isocyanurate are three, but the actual number of functional groups of the multifunctional isocyanurate may be rather small (eg, 2.5 to 3.0), which is also recognized as being within the scope of the present invention.

As a result of the foregoing reaction, the first monomer may comprise a compound having the formula

Formula I

In the above formula,

R ₁ and R ₂ are H or CH ₃ ,

R ₃ and R ₄ may each be an alkyl group having 1 to 12 carbon atoms (straight, branched or cyclic) or

R ³ and R ⁴ together may form a divalent cycloalkanediyl, oxacycloalkanediyl or azacycloalkanediyl linking group having from 2 to 12 carbon atoms,

Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ and Z ₆ are each a divalent group having 1 to 18 carbon atoms, preferably an alkanediyl group having 1 to 18 carbon atoms (straight, branched or Cyclic), most preferably a straight alkanediyl group having 1 to 4 carbon atoms.

Polyfunctional isocyanate trimers useful for the production of polyfunctional isocyanurates are preferably low viscosity polyfunctional aliphatic polyisocyanate resins. The polyfunctional isocyanurate is preferably a trimer of aliphatic diisocyanate, more preferably a trimer derived from hexamethylene diisocyanate (HDI). In the preparation of the first monomer, it has been found that the above-mentioned multifunctional isocyanurate is important for forming a transparent and almost colorless coating by UV curing. Further, typically, compositions based on these multifunctional isocyanurates cure rapidly in the air (eg, up to 1 minute) when exposed to low intensity UV light.

Suitable polyfunctional isocyanurates are readily synthesized by oligomerization of diisocyanates (eg HDI), as known in the art, to provide the trimers described above. Suitable products based on HDI derived isocyanurate are commercially available under the tradename DESMODUR N-3300. In addition, allophanated trimers derived from the reaction of HDI with butanol are suitable for use in the present invention and are sold under the trade names DESMODUR XP 7100 and DESMODUR XP 7040. The above isocyanate trimers are commercially available from Industrial Chemical Division of Bayer Corporation, Pittsburgh, Pennsylvania. It is desirable to minimize the amount of allophanate in order to improve the performance of the resulting cured coating. Low viscosity aliphatic isocyanate diluents can be treated in the same conditions and used in a similar manner. DESMODUR XP 7100 monomers are most preferred to preferably combine the performance characteristics of the finished coating with the reduced viscosity of the coating composition.

Multifunctional isocyanurate as used herein has three different reactive isocyanate groups suspended from the isocyanurate ring. Each of these isocyanate functional groups may react with the hydroxyl groups of both tertiary amine alcohols and hydroxyalkyl acrylates to form the first monomer.

Tertiary amine alcohols suitable for use in the present invention are acyclic (hydroxyalkyl) dialkylamines having 3 to 30 carbon atoms, such as N, N-dimethylaminoethanol, N, N-dimethylaminopropanol, N , N-dimethylaminobutanol, N, N-dimethylaminohexanol, N, N-dimethylaminododecanol, N, N-diethylaminoethanol, N, N-diethylaminopropanol, N, N-diethyl Aminobutanol, N-ethyl-N-methylaminopropanol, N-ethyl-N-hexylaminoethanol and the like; Acyclic (hydroxyalkyl) dialkylamines having 3 to 30 carbon atoms, for example 2-aziridinylethanol, 2-azetidinylethanol, 2-piperidinoethanol, N-methyl-4-azacyclo Hexanol and the like; Polyamino alcohols having 3 to 30 carbon atoms, for example, N-methylpiperazinoethanol, N-butylpiperazinoethanol, N-methylpiperazinobutanol and the like. (Hydroxyalkyl) alkylarylamines and (hydroxyalkyl) diarylamines can also be used in the present invention, their use being undesirable since the compositions comprising aromatic amines tend to discolor upon curing. Tertiary amine alcohols, including the examples described above, may be synthesized according to known methods or may be manufactured by Texas, Corp., Houston, TX, Ashland Chemical Company, Columbus, USA, or Aldrich Chemical, Milwaukee, WI. It can also be purchased from many manufacturers, such as a company.

In addition to the tertiary amine alcohols described above, about 2 moles of hydroxyalkyl acrylate are reacted with about 1 mole of polyfunctional isocyanurate. The hydroxyl groups of hydroxyalkyl acrylates react with isocyanates such that the main reaction product comprises acrylate groups suspended in the isocyanurate ring. Double bonds of these acrylate groups provide reaction sites that can form additional bonds with other monomers during the polymerization reaction. Suitable hydroxyalkyl acrylate compounds include various acrylic compounds including hydroxyalkyl acrylates, N-hydroxyalkyl acrylamides, and the like. Preference is given to hydroxyalkyl acrylates, in particular hydroxyalkyl acrylates comprising C ₁ to C ₄ hydroxyalkyl moieties. Particular preference is given to hydroxyalkyl acrylates, which are commercially available from the Dow Chemical Company, Midland, Michigan, USA.

Second monomer

The aforementioned first monomer can be polymerized by reaction with at least one additional radiation curable monomer (second monomer). Exposure to ultraviolet light in the presence of an appropriate amount of photoinitiator reacts the first monomer with the second monomer to form a highly crosslinked polymer coating suitable for use as a floor finish or the like.

This second monomer can be selected from a variety of radiation-sensitive polymerizable monomers and combinations thereof, including monofunctional, difunctional and trifunctional acrylates as well as more functional acrylates. The second monomer is preferably selected from difunctional acrylates or trifunctional acrylates and combinations thereof. Suitable bifunctional or trifunctional acrylates are commercially available from Sartomer Company, West Chester, Pennsylvania. The second monomer (s) are chosen to achieve the desired balance of properties in the cured coating as well as in the uncured composition. Suitable acrylates for use in the present invention include tetrahydrofurfuryl acrylate, cyclohexyl acrylate, n-hexyl acrylate, 2-ethoxyethyl acrylate, isodecyl acrylate, 2-methoxyethyl acrylate, 2 -(2-ethoxyethoxy) ethyl acrylate, stearyl acrylate, lauryl acrylate, octyl acrylate, 2-phenoxyethyl acrylate, glycidyl acrylate, isobornyl acrylate, benzyl acrylate Mono acrylates such as tridecyl acrylate, caprolactone acrylate, ethoxylated nonylphenol acrylate, polypropylene glycol acrylate, and the like; Triethylene glycol diacrylate, ethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, diethylene glycol diacrylate Diacrylates such as acrylate, hexanediol diacrylate, neopentyl glycol diacrylate, tripropylene glycol diacrylate, ethoxylated bisphenol A diacrylate, propoxylated neopentyl glycol diacrylate and the like; Trimethylolpropane triacrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, ethoxylated trimethylolpropane triacrylate, pentaerythritol triacrylate, propoxylated trimethylolpropane triacrylate, prop Triacrylates such as foxed glyceryl triacrylate and the like; High functional acrylates such as pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, and the like; Metal acrylates such as zinc diacrylate, calcium diacrylate and the like; Acrylates such as polyurethane monoacrylate, polyurethane polyacrylate, polyester monoacrylate, polyester polyacrylate, polyamide monoacrylate, polyamide polyacrylate, polybutadiene monoacrylate, polybutadiene polyacrylate, and the like. Oligomers and polymers; And acrylated silicones such as those sold under the trade names "EBECRYL 350" or "EBECRYL 1360" by UCB Radcure, Smirna, GA, USA, but are not limited thereto.

The second monomer may comprise a material other than an acrylated monomer, preferably a material which can be readily copolymerized with an acrylate monomer such as the aforementioned acrylated first monomer used in the present invention. Suitable materials include N-vinyl monomers such as N-vinylformamide, N-vinylpyrrolidone, N-vinylcarbazole, styrene monomers such as styrene, α-methylstyrene, vinylpyridine, and the like, and vinyl ethers, allyl ethers. (Eg, triallyl isocyanurate), other monomers such as allyl acrylate and ether maleate ester.

The acrylated material is preferred for use as the second monomer in the present invention. Ethoxylated trimethylolpropane triacrylate (e.g. available under the trade names "SR 454", "SR 499", "SR 502" and "SR 9035" from Sartomer Co.) and propoxylated diacrylate (e.g. tri Propylene glycol diacrylate) is most preferred.

As mentioned above, the second monomer (s) together with the first monomer are added to the reaction mixture and polymerized to form a hard and durable transparent coating of the invention, as further described below. In the reaction mixture, the wt% of the second monomer is typically from about 5 wt% to about 90 wt%, preferably from about 35 wt% to about 70 wt%, more preferably from about 45 wt% to about 65 wt% It is in range. The first monomer is present in the mixture at a concentration of about 10% to about 90% by weight, preferably about 25% to about 60% by weight, more preferably about 30% to about 50% by weight.

Photoinitiator

As mentioned above, the photoinitiator is added to the composition of the present invention to initiate the polymerization reaction. Preferred photoinitiators are free radical initiators for ultraviolet curing. Suitable photoinitiators for use in the present invention include high molar absorbance at maximum power to the light source (e.g. extinction coefficient), low color and low coloration tendency after UV exposure, shelf life stability, low odor and refreshing odor, and polymerization Selection is made with attention to features such as high efficiency for photoinitiation of the reaction. In order to cure the composition of the present invention quickly and satisfactorily, it has high molar absorbance (eg, 10,000 L / mole-cm or more) at one wavelength of the light source, while lower molar absorbance at another wavelength or the second wavelength of the light source. Preference is given to photoinitiators having (eg, 10,000 L / mole-cm or less). The photoinitiator of the composition of the present invention has an absorbance for a 25 μm film of about 2.5 or more at one wavelength (typically 254 nm), thereby rapidly surface curing, while absorbance at longer wavelengths (typically 350-370 nm) Is from about 0.05 to about 0.8, preferably from about 0.4 to about 0.6, preferably at a concentration sufficient to ensure fast and efficient curing.

Photoinitiators useful in the present invention include those known to be useful for UV curing of acrylate polymers. Such photoinitiators include benzophenone and derivatives thereof, benzoin, α-methylbenzoin, α-phenylbenzoin, α-allylbenzoin, α-benzylbenzoin, benzoin ether [e.g. benzyl dimethyl ketal (New York, USA) Sold under the trade name "IRGACURE 651" from Ciba-Geigy, Adslay, Ltd.), benzoin methyl ether, benzoin ethyl ether, benzoin n-butyl ether], acetophenone and derivatives thereof [e.g. 2-hydroxy -2-methyl-1-phenyl-1-propanone (available under the trade name “DAROCUR 1173” from Ciba-Geigy, Adslay, NY, USA) and 1-hydroxycyclohexyl phenyl ketone (HCPK) (Chiba-ga Sold under the trade designation "IRGACURE 184" in Igi Corporation)], 2-methyl-1- [4- (methylthio) phenyl] -2- [4-morpholinyl) -1-propanone (Ciba-Geigi Commercially available under the trade designation "IRGACURE 907"), 2-benzyl-2- (dimethylamino) -1- [4- (4-morpholinyl) phenyl] -1-butanone (Ciba-Geigi Co.); Opole In may be mentioned commercially available) under the trade name "IRGACURE 369". Other useful photoinitiators include pivaloin ethyl ether, anisoin ethyl ether, anthraquinones such as 2-methylanthraquinone, 2-ethyl anthraquinone, 2-t-butyl anthraquinone, 1-chloroanthraquinone, 2-bromo Anthraquinone, 2-nitroanthraquinone, anthraquinone-1-carboxaldehyde, anthraquinone-2-thiol, 4-cyclohexylanthraquinone, 1,4-dimethylanthraquinone, 1-methoxyanthraquinone, benzanthraqui Nonhalomethyl triazine, onium salts, for example diazonium salts such as phenyl diazonium hexafluorophosphate, diaryl iodonium salts (e.g., ditolyliodonium hexafluoroantimonate, etc.), sulfonium salts ( Eg triphenylsulfonium tetrafluoroborate, etc.), titanium complexes [eg, bis (η ₅ -2,4-cyclopentadien-1-yl) bis [2,6-difluoro-3- (1H- Pyrrole-1-yl) phenyl] titanium (available under the trade name "CGI 784 DC" from Ciba-Geigi Corporation)], uranyl Salts (e.g. uranyl nitrate, uranyl propionate), halomethylnitrobenzene (e.g. 4-bromomethylnitrobenzene, etc.), mono and bis-acylphosphines (e.g. Ciba-Geigy Co., Ltd.) Commercially available under the trade names "IRGACURE 1700", "IRGACURE 1800", "IRGACURE 1850" and "DAROCUR 4265". Other photoinitiators not listed herein may also be suitable for the present invention. Suitable photoinitiators can be selected by those skilled in the art.

Preferred photoinitiators used in this composition are a combination of about 4 parts by weight of benzophenone (based on the total composition weight) and 1 part by weight of N-ethylcarbazole or N-vinylcarbazole. Another preferred photoinitiator includes a combination of about 4 parts by weight of benzophenone and 1 part by weight of benzoin dimethyl ketal (based on the total composition weight). The photoinitiator is preferably present in the composition of the present invention at a concentration of about 2% to about 10% by weight, more preferably about 4% to about 7% by weight.

Other Ingredients

Additional optional ingredients may be included in the coating composition of the present invention. For example, a small amount of a hydrating agent may be added to the coating composition in order to coat uniformly on a suitable substrate. Suitable hydrating agents include, for example, fluorinating reagents such as the trade names "FLUORAD FC-431" and "FLUORAD FC-171" sold by 3M, St. Paul, Minn., USA.

When filler is added to the coating composition of the present invention, the wear properties can be altered. Fillers known to be useful in acrylate clear coating applications can be used in the present invention. Preferred fillers include those in which the silica particles are modified with 3-mercaptopropyltrimethoxysilane.

Other ingredients include antifoaming agent, leveling agent, anti-scratching agent, anti-slip agent, anti-foaming agent, antioxidant, light stabilizer (e.g. benzotriazole light stabilizer, hydroxybenzone) Phenone light stabilizers and the like), optical brighteners and other known compounding additives.

Preparation and Use of Coating Composition

In the coating composition of the present invention, it is preferable to prepare the first monomer first and then combine it with the second monomer, photoinitiator and other components.

In the preparation of the first monomer, polyfunctional isocyanurate is first added to the reaction vessel together with a suitable catalyst such as dibutyltin dilaurate. A mixture is prepared by adding tertiary amine alcohol and hydroxy alkyl acrylate. Suitable preservatives such as butylated hydroxytoluene (BHT), which are not consumed during the reaction, may also be added to the reaction mixture. A mixture of tertiary amine alcohol, hydroxyalkyl acrylate, and preservative is added to the reaction vessel, which contains the first monomer. The temperature of the reaction mixture is controlled while the reaction is completed at ambient conditions in air, preferably below about 40 ° C. to prevent preservatives from being consumed in advance. Thereafter, the reaction mixture is cooled to room temperature. Completion of the reaction can be monitored by any suitable means, such as an infrared spectrometer.

The first monomer thus prepared can then be combined with a second monomer, photoinitiator and other optional components in a suitable reaction vessel to provide a coating composition of the present invention. Particularly preferred coating compositions of the present invention comprise about 42 parts by weight of the first monomer (preferably DESMODUR XP 7100 isocyanurate available from Bayer Corporation), ethoxylated trimethylolpropane triacrylate (Sartomer Co., Ltd.) Sold under the trade name “SR-499”) about 48 parts by weight, about 5 parts by weight tripropylene diacrylate, about 5 parts by weight photoinitiator, about 0.3 parts by weight of a suitable hydrating agent (e.g., FLUORAD FC-171 sold at 3M) Parts and about 0.5 parts by weight of acrylated silicone (trade name EBECRYL 350, available from UCB Radcure, Simirna, GA, USA).

Inhibitors may be added to extend the shelf life of the compositions of the present invention. Suitable inhibitors include any substance known to inhibit free radical induced polymerization reactions, for example phenols of sterically hindered structures such as butylated hydroxytoluene (BHT) and derivatives thereof, hydroquinones such as methylhydroquinone and derivatives thereof, and N-nitrosophenylhydroxyhydroxylamine ammonium salts sold by Wako Chemicals USA Inc. (Richmond, VA) under the trade designation "Q-1301", but are not limited to these. Among these, N-nitrosophenylhydroxylamine aluminum salt is preferable.

The composition can then be coated onto a suitable substrate, such as conventional polyvinyl chloride floor tiles. After coating on the substrate, the coating composition is exposed to UV light to cure the composition with a cured protective coating. Those skilled in the art will be able to select a suitable light source. In general, a light source with a high intensity is preferable for rapidly curing the coating composition. However, when applying the coating composition to an already installed floor, low intensity UV light can be practical, and the coating composition of the present invention can be easily cured by simply exposing to low intensity UV light. Generally, a suitable UV light source of low intensity is one that emits one or more bands having a wavelength of about 300 nm or less. In order to quickly cure the applied coating, the light source preferably emits a second band having a wavelength of about 300 nm to about 400 nm. If the coating thickness is about 0.03 mm, a UV light source emitting a narrow band with a center wavelength around 254 nm at an intensity of about 5 mW / cm 2 to about 15 mW / cm 2 (on the surface of the coating) is suitable. The low intensity light source also preferably emits a second narrow band having a center wavelength in the range of 360 to 370 nm, typically about 365 nm, with the same appropriate intensity as described above. At the low UV intensities described above, the compositions of the present invention are cured, usually within 30 seconds, preferably within 20 seconds. These light sources are described in the following examples.

It is recognized that the overall shape of the light source is not within the scope of the present invention. Curing of the composition of the present invention can be performed using various light sources, such as a pulsed xenon flash light source, a medium pressure mercury light source, a low pressure mercury fluorescent light source, and a 300 nm fluorescent light source. It is also appreciated that longer wavelength lamps can be used to initiate the polymerization reaction when suitable photoinitiators are used.

When the coating composition of the present invention is applied to a suitable substrate, it is preferred to apply the composition to form a coating that is thinner than about 1.3 mm thick in order to promote curing of the composition within the time limits mentioned above. A number of any known application methods such as roll coating, squeegeeing, knife coating, curtain coating, spray coating and the like can be used to coat these thicknesses. In applying the above-mentioned composition to a substrate, suitable substrates include those which have been previously coated or sealed or conventional floor tiles which have not been previously coated or sealed. When the substrate to be coated is a vinyl tile or the like, it is preferable to first treat the substrate with a primer or sealant before applying the UV curable composition of the present invention to the substrate. By treating the substrate with a primer, the UV cured coating can then be more easily removed from the tile or other substrate. For example, chemical stripping agents can be used. In order to improve the adhesion of the coating composition to the substrate, it is most preferable to use an acrylated latex primer. The acrylated latex compositions useful in the present invention should contain at least one free radically polymerizable group suspended in each latex particle, preferably at least one. The latex is hydrophobic but may contain some hydrophilic groups.

When the primer is applied to the substrate, the solid content of the primer is controlled on the surface of the substrate using more than the amount of primer required to make the barrier layer with the desired adhesiveness while controlling the solid content of the primer to the extent required to make the film. It is desirable to provide a film. Typically, the solids content of the primer required as a wipe (eg manual) on the coating is from about 2% to about 40% by weight, preferably from about 2% to about 20% by weight, more preferably about 4% by weight. To about 15% by weight. Wetting or defoamers can be added to the latex emulsion to improve coating properties. The amount of such additives depends on the nature of the substrate and the concentration of the latex emulsion.

Preferred latex emulsions for use as primers of the present invention are acrylated emulsions sold under the trade designation "ROSHIELD 3120" by the Rohm and Haas Company, Philadelphia, Pennsylvania, USA. This emulsion is commercially available at a solids content of about 40.5% by weight, and suitable primers can be prepared by diluting the concentrated emulsion to a dilution weight ratio of up to about 9: 1 (water: emulsion). Certain formulations or the aforementioned ROSHIELD 3120 acrylated latex with a second primer polymer, preferably a styrene maleic anhydride (SMA) copolymer (trade name “SMA 1000A” available from Atochem Inc., Malvern, Pa.), More preferred are aqueous primer compositions comprising an ammonium salt of 38.5% solids content. The weight ratio of the acrylate to the SMA copolymer in the primer is preferably about 7: 1 to about 12: 1, more preferably about 10: 1. Small amounts of surfactant may also be added to the primer. Particularly preferred primers have a solids content of about 10 wt%, about 24.4 wt% ROSHIELD 3120 acrylated latex, about 73.2 wt% water, about 2.4 wt% SMA 1000A copolymer and about 0.02 wt% surfactant or hydrating agent (E.g., sold under the trade name "FLUORAD FC-129" at 3M in St. Paul, Minnesota, USA).

The primer may be applied to the substrate by any suitable method such as wiping, brushing, spraying and the like. After the latex is typically dried under ambient conditions, the UV curable composition of the present invention is applied thereon to cure in the manner described above. For example, a substrate such as a PVC tile coated with an acrylated latex primer described above and then coated with a UV curable acrylate (e.g., coating composition) can be easily stripped using a benzyl alcohol stripping agent as described in the following examples. have. Stripping takes place on the surface of the tile, so the stripped tile has a very good appearance. Corresponding tiles that are not primed, coated with the same UV curable acrylate, strip more slowly and do not generally strip cleanly (eg, at the substrate surface).

In one aspect of the invention described above, the primers may constitute one component of a floor finishing system that includes all of the primers as well as the coating compositions described above. Although a primer comprising ROSHIELD 3120 acrylated latex as described above is preferred, other commercially available materials may also be used as primers on certain substrates, such as PVC composition floor tiles. . Some suitable primers include a variety of commercially available bottom sealants, such as the trade names “CORNERSTONE” (3 M in St. Paul, Micron, USA), “TOPLINE” (3 M product) and “TECHNIQUE” (Milwaukee, WI). SC Johnson, Inc.). In addition, the primers described above, in particular primers comprising ROSHIELD 3120 acrylated latex, may be used for other applications besides the field of floor finishing in which any of a variety of UV polymerizable polymers (eg, excluding the coating compositions described above) are applied to the substrate. Thus, systems and methods are provided for coating various substrates with a UV curable polymer using primers. The coatings produced in these systems and methods adhere well to the substrate and can also be easily removed from the substrate by using suitable stripping compositions. When using an unacrylated latex primer, it is preferable to use a primer having a surface tension of 40 dyne / cm or more.

The cured coating of the present invention can be stripped from the substrate to which it is applied using a suitable stripper. The stripping agent is preferably a pH neutral formulation comprising a solvent, a coupling agent (eg hydrotrope) and water. If necessary, dyes, fragrances and thickeners may be added to the strip composition. Stripping compositions effective for the floor finishing composition of the present invention include those described in the following test methods.

material

The components used in the examples are as follows.

DESMODUR N3300 is a trade name for hexane diisocyanate trimers available from Bayer Corporation, Industrial Chemicals Division.

DESMODUR XP 7100 is a trade name for an allophaned hexane diisocyanate trimer mixture available from Bayer Corporation, Industrial Chemicals Division.

DESMODUR XP 7040 is a trade name for an allophaned hexane diisocyanate trimer mixture available from Bayer Corporation, Industrial Chemicals Division.

SR 306 is a trade name for tripropylene glycol diacrylate, a bifunctional acrylate monomer available from Sartomer Co., West Chester, Pennsylvania.

SR 335 is a trade name for lauryl acrylate, a monofunctional acrylate monomer commercially available from Sartomer Company, West Chester, Pennsylvania.

SR 454 is a trade name for ethoxylated trimethylolpropane triacrylate, a trifunctional acrylate monomer commercially available from Sartomer Co., West Chester, Pennsylvania.

SR 499 is a trade name for ethoxylated trimethylolpropane triacrylate, a trifunctional acrylate monomer commercially available from Sartomer Company, West Chester, Pennsylvania.

DAROCUR 1173 is a trade name for 2-hydroxy-2-methyl-1-phenylpropan-1-one, a photoinitiator marketed by Ciba-Geigy, Adslay, NY.

DAROCUR 4265 is a trade name for acylphosphine, a photoinitiator marketed by Ciba-Geigy, Adslay, NY.

IRGACURE 184 is a trade name for 1-hydroxycyclohexyl phenyl ketone, a photoinitiator marketed by Ciba-Geigy, Adslay, NY.

FLUORAD FC-431 is a trade name for a hydrating agent sold by 3M in St. Paul, Minnesota, USA.

FLUORAD FC-171 is a trade name for a hydrating agent sold by 3M in St. Paul, Minnesota, USA.

PVC tiles are standard floor tiles that include polyvinyl chloride stripped and washed to remove factory finishes.

Sealed PVC tiles are standard floor tiles comprising polyvinyl chloride coated with a floor finish or sealant after stripping and washing to remove factory finishes.

ROSHIELD 3120 is a trade name for a 40.5% by weight solidified acrylate emulsion commercially available from the Rohm and Haas Company, Philadelphia, Pennsylvania, USA, where the concentrate is diluted with a water ratio of 9: 1 (water: emulsion) to primer. Use as.

EBECRYL 350 is a trade name for acrylated silicone available from UCB Radcure, based in Simirna, Georgia.

TECHNIQUE is a trade name for an acrylic floor sealer marketed by SC Johnson, Milwaukee, Wisconsin.

TOPLINE is a trade name for an acrylic floor finish sold by 3M in St. Paul, Minnesota, USA.

CORNERSTONE is a trade name for an acrylic floor finish sold by 3M in St. Paul, Minnesota, USA.

Preparation process

The following procedures are described in the Examples as to prepare the materials used.

Preparation of Oligomer A

A dry 5 L reaction vessel was equipped with a drying tube, addition funnel, thermometer and mechanical stirrer, and the vessel was charged with 450.0 g (2.30 equiv) of hexane diisocyanate trimer (DESMODUR N 3300). Four drops of dibutyltin dilaurate were added to the reaction vessel. A mixture was prepared by mixing 68.43 g (0.77 equiv) of 2- (N, N-dimethylamino) ethanol, 178.3 g (1.54 equiv) of 2-hydroxyethyl acrylate and 0.35 g of methylhydroquinone as preservatives. This mixture was added to the reaction vessel and at the same time the temperature of the contents was kept below 35 ° C. When the mixture was cooled to room temperature it was separated by pouring it into a vessel. Infrared analysis confirmed the presence of only traces of isocyanate or free alcohol. The material was viscous and needed a spatula to dispose of.

Preparation of Oligomer B

A dry 5 L reaction vessel was equipped with a drying tube, addition funnel, thermometer and mechanical stirrer and charged with 600.0 g (2.93 equiv) of allophanated hexane diisocyanate trimer (DESMODUR XP 7100). A mixture was prepared by mixing 87 g (0.975 equiv) of 2- (N, N-dimethylamino) ethanol, 226.7 g (1.95 equiv) of 2-hydroxyethyl acrylate and 0.45 g of BHT as preservatives. 9 drops of dibutyltin dilaurate were added to the reaction vessel. This mixture was added to the reaction vessel and at the same time the temperature of the mixture was kept below 30 ° C. When the mixture was cooled to room temperature it was separated by pouring it into a vessel. Infrared analysis confirmed the presence of only traces of isocyanate or free alcohol. This material was as viscous as Ween, making it difficult to swell.

Preparation of Oligomer C

A dry 5 L reaction vessel was equipped with a drying tube, addition funnel, thermometer and mechanical stirrer and charged with 642 g (3.018 equiv) of allophanated hexane diisocyanate trimer (DESMODUR XP 7040). 6 drops of dibutyltin dilaurate was added to the reaction vessel. A mixture was prepared by mixing 89.7 g (1.01 equiv) of 2- (N, N-dimethylamino) ethanol, 233.7 g (2.012 equiv) of 2-hydroxyethyl acrylate and 0.48 g of BHT as preservatives. This mixture was added to the reaction vessel and at the same time the temperature of the contents was kept below 40 ° C. When the mixture was cooled to room temperature it was separated by pouring it into a vessel. Infrared analysis confirmed the presence of only traces of isocyanate or free alcohol. This material is low in viscosity and therefore easily poured.

Preparation of Modified Silica Particles

Mercapto-functionalized silica was prepared. 1176 g of an aqueous dispersion of colloidal silica with a solids content of 34% by weight and a pH of 3.2 (available under the trade name NALCO 1042 from Nalco Chemical Company, Naperville, Ill.) In distilled water with a total solid content of 10% Dilution to give a total of 4000 g. To this was added 19.6 g of (3-mercaptopropyl) trimethoxysilane (commercially available from Aldrich Chemical Company, Milwaukee, WI). The resulting suspension was heated to 80 ° C. for 18 hours with stirring to give a translucent colorless suspension which was used without purification. One fraction (50 g) of the aforementioned suspension was mixed with 45 g of SR 499 to obtain a slurry. Water was removed at room temperature under vacuum (aspirator / rotary evaporator) to give 50 g of a clear liquid.

General process

Curing Process A

Dissipates 110 V power with a front mounted downward facing bank of 18 in (45.7 cm) fluorescent lights in a 1.5 in (3.81 cm) center about 1 in (2.54 cm) from the floor UV exposure equipment was installed using wheeled carts. A fluorescent lamp was cantilevered in front of the cart wheels to move forward on the uncured bottom coating without damaging the finish. A reflective aluminum sheet was mounted behind the fluorescent lamp to direct radiant energy toward the coating. There were two sets of lamps in the bank. The first set consists of two 15 watt fluorescent tubes on a 25 watt ballast in front of the bank. These two fluorescent lamps consist of one 15 watt germicidal lamp (low pressure mercury lamp emitting at about 254 nm) and one 15 watt black light (365 nm). The second set consists of six 15 watt fluorescent tubes on a 15 watt ballast. The second set is located in the bank with a 2 in spacing between the two sets of fluorescent tubes. The second fluorescent lamp set alternates a total of six germicidal and black lamps in the second set.

All sterilizing bulbs are commercially available from General Electric under the trade name "F15T8". Black light bulbs are also available from General Electric under the trade name "F15T8 / BL". The power was measured at the center of the bulb of the sterile bulb surface, which was about 11 mW / cm 2 for the 25 watt ballast and about 7 mW / cm 2 for the 15 watt ballast. The power was measured at the black light bulb surface and at the bulb center, which was about 7 mW / cm 2 for 25 watt ballast and about 4.5 mW / cm 2 for 15 watt ballast.

Unless otherwise noted, all samples were cured by exposure to the light source for 30 seconds.

Curing Process B

UV exposure equipment was installed using a downward facing bank of 18 in fluorescent lamps at a 1.5 in center about 1 in from the bottom. A reflective aluminum sheet was mounted behind the fluorescent lamp to direct radiant energy toward the coating. The lamp set consists of six sterile bulbs.

The bulbs are all sold by General Electric under the trade name "F15T8". The power was measured at the bulb surface bulb center, which was about 7 mW / cm 2.

Unless otherwise noted, all samples were cured by exposure to the light source for 30 seconds.

Cloth process A

In applying the coating composition to a substrate such as a PVC tile or a sealed PVC tile, a small volume of the composition, typically about 2 g to about 3 g, was applied to the substrate using a syringe. The composition was then rolled onto the desired sections on the substrate using a manual rubber roller until the applied composition was coated fairly homogeneously on the desired sections of the substrate. Thereafter, the composition was cured. To determine the coating weight, the weight of the coated tile was compared to the original tile weight (eg, before applying the coating composition).

Test Methods

In the following examples, the following test method was used.

Test Method A (Taber Wear Resistance)

A 4 "x 4" square sample was prepared consisting of the coated material to be tested. Use a template to pinpoint one spot on the coating that is expected to wear out, and use the Byk-Gardner Micro-Tri-Gloss meter (Bik-Gardner, Silver Spring, Maryland) for the first time on each side Of 20 ° or 60 ° gloss was read (total 4 reads). The sample was then mounted on a Taber standard wear tester (model number 503 of Teletine Tab, North Towana, NY) with a vacuum adder, 500 g wheel weights and CS-10f wheels. The sample was worn 100 times and the gloss after wear was measured as described above. The gloss retention (%) for each side was calculated and the results averaged.

Test Method B (Scratch Hardness)

Scratch hardness was measured using a Byk-Gardner pencil scratch tester (Bike-Gardner, Silver Spring, MD). Measured reproducibly to about ± 100 g. The result generally depends on the thickness of the substrate and the film.

Test Method C (Strip Time)

In the coating test of the present invention, which measures the time taken to strip a radiation cured coating from a substrate, the coating was stripped from the tile substrate using the following formulation: 68.75 parts deionized water, 22.50 parts benzyl alcohol, n-octyl 5.52 parts by weight of amine, 3.24 parts by weight of glycolic acid, 0.02 part by weight of surfactant ("FLUORAD FC-129" sold by 3M).

A stripper was applied to drop in many spots on the cured coating. The recorded strip time is either the time the film is lifted over the entire area covered by the strip (1) or the time it takes the strip to loosen the coating sufficiently to wipe the applied strip with a paper towel to create a clean stripped substrate surface (2). to be. State 1 is generally observed for coatings applied on sealed PVC tiles, while state 2 is generally observed for PVC tiles. The strip time is very variable and depends not only on the coating thickness but also on the degree of cure for the particular coating. As a result, care must be taken to compare strip time results for coatings with different thicknesses or coatings with different degrees of cure.

Test Method D (Glossy Measurement)

Gloss was measured using a calibrated Byk-Gardner Micro-Tri-Gloss meter (Bik-Gardner, Silver Spring, MD). The surface was cleaned and then read.

Test Method E (Color Measurement)

Colors were measured using a calibrated Datacolor International Microflash 200d spectrometer (Datacolor International, Challot, North Carolina) using a 1.5 cm aperture. All readings are the average of three measurements. As used herein, CIELAB color coordinates L ^* , a ^* , b ^* and color shift DE are known terms in color measurements.

The following examples are intended to illustrate the preparation, use and comparative advantages of the present invention and are not intended to limit the present invention. Unless otherwise noted, all parts and percentages are by weight.

Examples 1-15

Examples 1-15 were prepared and evaluated for durability according to test method A. The results were analyzed to find that compositions with reduced amounts of SR-306 bifunctional acrylate had optimal durability. All samples contained 0.3 parts by weight of FC-431 FLUORAD hydrate, and were coated on PVC tiles. It was coated with 2.5 g / ft ² (26.9 g / m ² ) according to coating procedure A and cured according to curing procedure A. The formulation and wear resistance of these examples are listed in Table 1 below.

Formulation example Oligomer A weight part SR-499 parts by weight SR-306 parts by weight DAROCUR 1173 parts by weight 20. Glossy retention rate% Standard Deviation One 50.00 35.00 15.00 5 74.0 4.8 2 30.00 45.00 25.00 5 43.1 8.1 3 40.00 42.50 17.50 5 67.0 2.6 4 40.00 35.00 25.00 5 63.5 3.0 5 35.00 50.00 15.00 5 70.9 3.4 6 40.00 35.00 25.00 5 66.3 3.2 7 40.00 42.50 17.50 5 74.2 1.9 8 50.00 40.00 10.00 5 78.2 1.7 9 45.00 45.00 10.00 5 77.8 1.5 11 40.00 50.00 10.00 5 77.2 1.4 12 50.00 40.00 10.00 5 76.4 3.5 13 30.00 45.00 25.00 5 64.1 3.0 14 30.00 50.00 20.00 5 56.1 3.4 15 45.00 35.00 20.00 5 64.2 2.1

Example 16

A series of samples was prepared based in part on the data described above for Examples 1-15. Samples of Example 16 were 40 parts by weight of oligomer A, 45 parts by weight of trifunctional acrylate (SR-499), 10 parts by weight of bifunctional acrylate (SR-306), 0.3 parts by weight of hydrating agent (FLUORAD FC-431) and a photoinitiator. Prepared using 5 parts by weight. All 5 parts by weight of a photoinitiator or other photoinitiator, such as DAROCUR 1173 material, including 3 parts by weight of DAROCUR 1173 photoinitiator or 3 parts by weight of benzophenone combined with 2 parts by weight of IRGACURE 184 photoinitiator were used successfully. These compositions were coated onto a sealed PVC tile coated with a primer coating consisting of CORNERSTONE bottom sealant according to coating procedure A and cured according to curing procedure A. Abrasion resistance, scratch hardness and strip time were measured according to the test methods A, B and C described above. The gloss retention of 20 ° for these samples was maintained at about 83%. The scratch hardness was about 1200 g. Strip time was 5 minutes or less.

Examples 17-30

Examples 17-30 were prepared and evaluated for durability according to test method A. The results were analyzed to find that compositions with reduced amounts of SR-306 bifunctional acrylate had optimal durability. All samples contained 0.3 parts by weight of hydrating agent (FLUORAD FC-431), which was coated on PVC tiles. It was coated with 2.5 g / ft ² (26.9 g / m ² ) according to coating procedure A and cured according to curing procedure A. The composition and wear resistance of these examples are listed in Table 2 below.

Formulation example Oligomer B parts by weight SR-499 parts by weight SR-306 parts by weight DAROCUR 1173 parts by weight 20. Glossy retention rate% Standard Deviation 17 60 30 5 5 66.7 0.4 18 60 30 5 5 68.1 1.0 19 45 45 5 5 75.1 8.3 20 45 35 15 5 48.8 6.4 21 45 30 20 5 51.2 4.3 22 41.25 41.25 12.5 5 62.3 1.1 23 45 45 5 5 73.4 2.2 24 45 30 20 5 60.7 1.9 25 30 45 20 5 7.6 5.2 26 30 60 5 5 72.9 2.3 27 37.5 37.5 20 5 56.1 4.1 28 30 52.5 12.5 5 66.2 4.5 29 30 60 5 5 69.0 8.7 30 52.5 30 12.5 5 71.0 3.8

Example 31

A series of samples was prepared based in part on the data described above for Examples 17-30. All samples were prepared using 30 parts by weight of oligomer B, 65 parts by weight of trifunctional acrylate (SR-499), 0.3 parts by weight of hydrous (FLUORAD FC-431) and 5 parts by weight of photoinitiator. As photoinitiators, DAROCUR 1173 photoinitiators alone can be used successfully, as well as other photoinitiators, including benzophenones and DAROCUR 1173 photoinitiators and combinations of benzophenones and IRGACURE 184 photoinitiators. These samples were coated onto the substrate according to coating procedure A and cured according to curing procedure A. Abrasion resistance, scratch hardness and strip time were measured according to the test methods A, B and C described above.

Using an initiator system consisting of 5 parts by weight of DAROCUR photoinitiator and an additional 1 part by weight of benzophenone, the wear resistance after 15 seconds of irradiation was up to 82% with a 20 ° gloss retention. A typical scratch hardness of this composition is applied to a sealed PVC tile [poly (vinylidene chloride) primed polyester film bottom sealer sold under the trade name “TECHNIQUE” by SC Johnson, Milwaukee, WI). 800-1000 g. In the case of coating on the conventional floor finish, a thin layer phenomenon was observed even with a small force of 200 g. The strip time from the sealed PVC tiles (when sealed with a floor finish sold under the trade name “CORNERSTONE” at 3 M) was from about 2 minutes to about 3 minutes.

Example 32

A series of samples was developed based in part on the results of Example 16. These samples were 40 parts by weight of oligomer C, 45 parts by weight of trifunctional acrylate (SR-499), 10 parts by weight of difunctional acrylate (SR-306), 5 parts by weight of photoinitiator and 0.3 parts by weight of hydrating agent (FLUORAD FC-431). It is composed. Both DAROCUR 1173 photoinitiators or other photoinitiators, including combinations of benzophenones and DAROCUR 1173 photoinitiators and combinations of benzophenones and IRGACURE 184 photoinitiators, have been used successfully. These samples were coated onto the substrate according to coating procedure A and cured according to curing procedure A. Abrasion resistance, scratch hardness and strip time were measured according to the test methods A, B and C described above. Abrasion resistance (20% gloss retention) was maintained at 85%, scratch hardness was 1300 g, and strips from sealed PVC tiles (sealed with floor finish sold under the trade name "CORNERSTONE" at 3 M) The time was less than 5 minutes.

Examples 33-60

Examples 33-60 were prepared and evaluated for abrasion resistance according to test method A. All samples contained 0.3 parts by weight of hydrating agent (FLUORAD FC-431). The composition of the example was coated with a dry coat weight of 2.5 g / ft ² (26.9 g / m ² ) according to coating procedure A and cured according to curing procedure A. The compositions and wear resistance data of Examples 33 to 60 are listed in Table 3 below. The results were analyzed to find that compositions with reduced amounts of SR-335 monofunctional acrylates showed optimal durability.

Examples 33-60 Formulation example Oligomer A weight part SR-454 parts by weight SR-335 parts by weight DAROCUR 1173 parts by weight 20 ° gloss retention% 60% gloss retention% 33 45.00 35.00 20.00 5 62.50 67.88 34 30.00 20.00 50.00 5 Not curable Not hardenable 35 30.00 50.00 20.00 5 62.80 37.13 36 35.00 25.00 40.00 5 Not hardenable Not hardenable 37 30.00 50.00 20.00 5 29.39 36.47 38 30.00 20.00 50.00 5 Not hardenable Not hardenable 39 45.00 35.00 20.00 5 48.56 56.81 40 35.00 40.00 25.00 5 53.81 59.69 41 60.00 20.00 20.00 5 57.43 68.23 42 60.00 20.00 20.00 5 46.32 57.15 43 30.00 35.00 35.00 5 Not hardenable Not hardenable 44 50.00 25.00 25.00 5 65.36 76.89 45 45.00 20.00 35.00 5 Not hardenable Not hardenable 46 40.00 30.00 30.00 5 Not hardenable Not hardenable 47 57.50 30.00 12.50 5 52.90 70.60 48 50.00 30.00 20.00 5 56.90 64.90 49 50.00 50.00 0.00 5 56.80 75.20 50 57.50 42.50 0.00 5 51.20 69.20 51 60.00 38.33 1.67 5 59.50 77.20 52 50.00 30.00 20.00 5 59.60 68.80 53 65.00 35.00 0.00 5 68.30 79.00 54 65.00 30.00 5.00 5 62.70 75.50 55 50.00 50.00 0.00 5 53.40 74.40 56 57.50 36.25 6.25 5 64.40 74.80 57 50.00 40.00 10.00 5 60.80 70.10 58 50.00 40.00 10.00 5 66.30 73.50 59 60.00 31.67 8.33 5 68.20 80.80 60 57.50 36.25 6.25 5 74.20 80.50

Example 61

A series of samples was developed based in part on the results of Examples 33-60. These samples included 177 parts by weight of oligomer A, 102 parts by weight of trifunctional acrylate (SR-454), 21 parts by weight of monofunctional acrylate (SR-335), 15 parts by weight of photoinitiator (DAROCUR 1173) and hydrated (FLUORAD FC- 431) 0.3 parts by weight. These formulations were coated onto PVC tiles according to coating procedure A and cured according to curing procedure A. Wear resistance, scratch hardness and strip time for these samples were measured according to the test methods A, B and C described above. The wear resistance was about 74% with a 20 ° gloss retention. Scratch hardness was 1700 g or more. The strip time was about 3 minutes.

Example 62

A coating composition was prepared comprising 60 parts by weight of oligomer A, 21 parts by weight of trifunctional acrylate (SR-454), 12 parts by weight of caprolactone acrylate and 2.4 parts by weight of photoinitiator (DAROCUR 1173). The sample was coated with a thickness of about 1 mil on the PVC tile according to coating process A and cured for 20 seconds according to curing process B. The resulting coating was tested for strip time according to test method C, which took about 8 minutes to strip.

Example 63

A coating composition was prepared comprising 60 parts by weight of oligomer A, 20 parts by weight of trifunctional acrylate (SR-454), 20 parts by weight of caprolactone acrylate, and 5 parts by weight of photoinitiator (DAROCUR 1173). The composition was coated on PVC tiles according to coating procedure A and cured according to curing procedure A. The resulting coatings were tested according to test methods A, B and C. The wear resistance was about 75% with a 60 ° gloss retention and a scratch hardness of about 500 g. The strip time from the PVC tiles was about 3 minutes.

Examples 64 and 65

Examples 64 and 65 were prepared as listed in Table 4 below. Example 65 was the same as for Example 64, except that it was prepared using functionalized silica prepared according to the preparation described above. The composition was coated on a PVC tile according to coating procedure A and cured according to curing procedure A to obtain a cured coating having a thickness of about 0.25 mm. The coating was tested for wear resistance according to Test Method A. With a 20 ° gloss retention value, it was found that the coating of Example 65 containing functionalized silica was slightly superior in wear resistance.

Examples 64 and 65 Example Furtherance 20 ° gloss retention% Standard Deviation 64 40 parts by weight of oligomer C, 45 parts by weight of trifunctional acrylate (SR-499), 10 parts by weight of difunctional acrylate (SR-306), 3 parts by weight of benzophenone, 2 parts by weight of DAROCUR 1173 photoinitiator 83.9 4.5 65 40 parts by weight of oligomer C, 45 parts by weight of trifunctional acrylate (SR-499) containing 10% functionalized silica, 10 parts by weight of difunctional acrylate (SR-306), 3 parts by weight of benzophenone, DAROCUR 1173 photoinitiator 2 Parts by weight 87.9 2.1

Examples 66-71

In order to measure the effect of visible light on the color of the cured coating produced in the present invention, a premix was prepared. The premix consists of 30 parts by weight of oligomer C, 65 parts by weight of trifunctional acrylate (SR-499), 5 parts by weight of photoinitiator as described below, and 0.3 parts by weight of hydrating agent (FLUORAD FC-431). These samples were coated with 2.5 g / ft ² (26.9 g / m ² ) on off-white PVC tiles and cured according to curing procedure A. However, hardening time was 15 second. The cured coating was exposed to a 6 × 15 W Philips F15T8BLB bulb (about 5 kW / cm 2, 350-370 nm) at a distance of about 1 in. The sample was then exposed to a 6 × 15 W Philips 15WTLD / 03 bulb (wavelength of about 420 nm) at a distance of about 1 in. CIELAB color coordinates L ^* , a ^* and b ^* were recorded.

L ^* represents white, positive a ^* coordinates represent red, and positive b ^* coordinates represent yellow. The DE value is a measure of the overall color deviation, indicating that DE of 1 to 2 or less is generally invisible to the naked eye. Based on the data listed in Table 5, it was confirmed that UV exposure causes reversible yellowing upon exposure to blue light.

Examples 66-71 Example Weight of premix Benzophenone parts by weight DAROCUR 1173 parts by weight Color coordinates after 15 second curing Color coordinates after 45 minutes curing at 350 to 370 nm Color coordinates after 40 minutes curing at 420 nm L ^* a ^* b ^* L ^* a ^* b ^* DE L ^* a ^* b ^* DE 66 9.5 0.0 0.5 87.82 1.03 4.67 86.84 1.17 8.72 4.17 86.91 1.20 5.91 1.55 67 9.5 0.1 0.4 88.25 1.01 4.81 86.92 1.19 8.31 3.75 87.00 1.16 5.61 1.49 68 9.5 0.2 0.3 88.31 1.01 4.74 87.06 1.11 7.19 2.75 86.99 1.14 5.56 1.56 69 9.5 0.3 0.2 88.25 1.00 4.79 87.00 1.12 7.04 2.58 86.94 1.10 5.55 1.52 70 9.5 0.4 0.1 87.61 1.06 5.04 86.98 1.19 7.83 2.86 87.06 1.11 5.66 0.83 71 9.5 0.5 0.0 87.60 1.04 4.91 86.93 1.18 7.81 2.98 87.00 1.09 5.67 0.97

Examples 72-80

As in the preparation of oligomer B, by combining 42 parts by weight of alloplanned HDI trimer (DESMODUR XP-7100), 2-hydroxyethyl acrylate and 2-dimethylamino-ethanol (equivalent ratio of 3: 2: 1) Oligomers were prepared. 48 parts by weight of trifunctional acrylate (SR-499), 5 parts by weight of bifunctional acrylate (SR-306), 3 parts by weight of benzophenone, 2 parts by weight of DAROCUR 4265 photoinitiator and a hydrous (FLUORAD FC-171) 0.3 to the oligomer. Combining parts by weight gave a UV curable coating composition. In some embodiments, EBECRYL 350 acrylated silicone was added to the coating composition as the release material.

The adhesion of the coating composition to both PVC tiles and sealed PVC tiles was tested. Sealed PVC tiles were prepared by applying primer or sealant by hand using gauze to provide a smooth and uniform coating. The primer was then dried in air at ambient temperature and ambient humidity.

Thereafter, the coating composition was applied to both the sealed PVC tile and the PVC tile according to the coating process A, and then UV cured by exposing for 10 seconds according to the curing process A. After the curing step, the cured coatings and primers (if present) were cut together with a razor blade to form a tile substrate consisting of a 1/8 "x 1/8" (0.32 cm x 0.32 cm) square grid. Tape was applied to the square pattern (" SCOTCH Rug and Carpet Tape " at 3M) using a 2.3 kg roller. The tape was then peeled off the tile by grasping the end of the tape by hand and pulling the back of the tape upward at an angle of about 180 degrees. A 0% adhesion value means that all of the coating is peeled off the tile, while a 100% adhesion value means that the coating is not removed. In general, all UV cured coatings adhere well to the tile substrate, which has been observed to have good adhesion to sealed PVC tiles, specifically tiles sealed with ROSHIELD 3120 latex.

Data on the composition of the UV curable coating, the primer layer used, and the adhesion test are summarized in Table 6. Unless otherwise specified, the coatings in these examples consisted of 100 parts by weight of the coating composition without addition of acrylated silicone.

Examples 72-80 Example primer Adhesion rate% 72 none 0 73 (100 parts by weight of coating + 1 part by weight of EBECRYL 350 acrylic silicone) none 0 74 TECHNIQUE 10 75 TOPLINE 0 76 ROSHIELD 3120 100 77 TOPLINE coated with ROSHIELD 3120 90 78 (100 parts by weight of coating + 1 part by weight of EBECRYL 350 acrylated silicone) ROSHIELD 3120 100 79 (100 parts by weight of coating + 2 parts by weight of EBECRYL 350 acrylated silicone) ROSHIELD 3120 100 80 (100 parts by weight of coating + 3 parts by weight of EBECRYL 350 acrylated silicone) ROSHIELD 3120 100

While the preferred embodiments of the present invention have been described in detail above, those skilled in the art will recognize that the foregoing embodiments may be modified and changed as described in the appended claims without departing from the spirit and scope of the invention.

Claims (44)

(b) a polyfunctional isocyanurate containing at least three terminal reactors reacted with (b) hydroxyalkyl acrylate and (c) tertiary amine alcohol, wherein the molar ratio of a: b: c is about 1 A monomer useful for producing a radiation curable coating composition, characterized in that: 1 to 2.5: 0.5 to 2, and b + c is the total number of terminal reactors of 3 to (a). Applying to the bottom a coating acrylated latex primer composition comprising an acrylated latex having a solids content of 2% to 40% by weight; Drying the primer composition to form an acrylic polymer primer coating on the bottom; (i) a polyfunctional isocyanurate containing (i) at least three terminal reactors reacted with (b) hydroxyalkyl acrylates and (c) tertiary amine alcohols, the molar ratio of a: b: c Is about 1: 1 to 2.5: 0.5 to 2 and b + c is a first monomer that is the total number of terminal reactors of 3 to (a); (ii) a second monomer comprising a radiation curable material; And (iii) applying a radiation curable coating composition containing a photoinitiator to the primer coating; And Forming a protective coating on the bottom by curing the composition by exposing the radiation curable coating composition to ultraviolet light; Method of applying a protective coating on the bottom comprising a. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete