Radiation-curable compositions for coating optical fibers with enhanced high-speed processability

Abstract

Radiation-curable compositions for coating optical fibers are disclosed herein. Disclosed and claimed are radiation-curable compositions containing a reactive oligomer component comprising the reaction product of a polyol, a diisocyanate, a hydroxyl-functional compound having at least one methacryloyl group, a compound having a hydroxyl group but no polymerizable group, and optionally a silane coupling agent, wherein a portion of the polymerizable groups comprises methacrylate groups; a reactive diluent monomer component, wherein a portion of the polymerizable groups comprises acrylate groups, acrylamide groups, or N-vinylamide groups, or a combination thereof; a photoinitiator; and optional additive components. Also described are methods for coating the radiation-curable compositions, and the resulting optical fiber coatings and cables.

Description

[Technical field]

[0001] The present invention relates generally to methods for coating optical fibers, radiation curable coatings suitable for use on optical fibers produced using high speed, low helium, and / or high temperature draw, and optical fibers produced therefrom.

[0002] [CROSS REFERENCE TO RELATED APPLICATIONS] This application claims priority to European Patent Application No. 19176577.5, filed May 24, 2019, which is incorporated herein by reference in its entirety as if fully set forth herein. [Background technology]

[0003] Optical fibers are used in a variety of applications and offer several advantages over other media. For example, data can be transmitted through optical fibers at higher data rates than wires. Optical fibers are also lighter and more flexible than wires. Thus, optical fibers, especially those made of glass, are often used for data transmission in the telecommunications industry. However, left unprotected, optical fibers are not suitable for field use because the thin glass strands through which the light signals are transmitted are prone to breakage. In addition to being susceptible to physical damage, uncoated optical fibers are also adversely affected by contact with moisture. As a result, optical fibers have long been coated with surface coatings to provide protection and ensure a high level of performance.

[0004] It is well known to draw glass fibers from specially prepared cylindrical preforms that are locally and symmetrically heated, for example to a temperature of about 2000° C. The preform is heated, such as by feeding it into a furnace, and the glass fibers are drawn from the molten material. After the glass fibers are drawn from the preform, preferably immediately after cooling, a surface coating composition is applied to the glass fibers. The coating composition is then cured to produce a coated optical fiber. General methods for applying a double layer of coating composition to a moving glass fiber are well known in the art and are disclosed in U.S. Pat. No. 447,830 to Taylor and U.S. Pat. No. 4,851,165 to Rennell et al. Newer fiber design concepts can be found in U.S. Pat. No. 8,837,892, U.S. Pat. Appl. Pub. No. 2014 / 0294355, and U.S. Pat. Appl. Pub. No. 2015 / 0071595.

[0005] To protect them, optical fibers are often coated with two or more superimposed radiation-curable coatings immediately after the fiber is produced by drawing. "Radiation-curable" means that radiation is required to initiate crosslinking of the composition, such as from a liquid (uncured) state to a solid (cured) state.

[0006] Typically, radiation curable optical fiber coatings are the cured product of a composition that includes a mixture of one or more components having one or more ethylenically unsaturated (C=C) bonds that undergo crosslinking by free radical polymerization under the influence of radiation. Such compositions also typically include a photoinitiator to assist in the radiation curing, especially when curing is accomplished by irradiation with ultraviolet (UV) wavelengths.

[0007] The coating that directly contacts the optical fiber is called the "inner primary coating" and the overlay coating is called the "outer primary coating". In some documents, the inner primary coating is also referred to simply as the "primary coating" and the outer primary coating is called the "secondary coating". The inner primary coating is typically formulated to have a significantly lower modulus than the secondary coating.

[0008] The relatively soft inner primary coating provides resistance to microbending, which is undesirable since it results in additional attenuation (i.e., signal loss) of the signal transmission of the coated optical fiber. Microbends are microscopic curvatures of the optical fiber that involve local axial displacements of a few micrometers and spatial wavelengths of a few millimeters. Microbends can be caused by thermal stresses and / or mechanical lateral forces. Coatings can provide lateral force protection to protect the optical fiber from microbending, but as the coating thickness decreases, the amount of protection provided decreases. The relationship between coatings and protection from transverse stresses leading to microbending has been discussed, for example, in D. Gloge, “Optical-fiber packaging and its influence on fiber straightness and loss”, Bell System Technical Journal, Vol. 54, No. 2, p. 245 (1975); W. B. Gardner, “Microbending Loss in Optical Fibers”, Bell System Technical Journal, Vol. 54, No. 2, p. 457 (1975); J. Baldauf, “Relationship of Mechanical Characteristics of Dual Coated Single Mode Optical Fibers and Microbending Loss”, IEICE Trans. Commun., Vol. E76-B, No. 4, 352 (1993); and K. Kobayashi, “Study of Microbending Loss in Thin Coated Fibers and Fiber Ribbons”, IWCS, 386 (1993). The harder outer primary coating, or secondary coating, provides resistance to handling forces such as those encountered when the coated fibers are formed into ribbons and / or cables.

[0009] Optical fiber secondary coating compositions generally comprise a mixture of ethylenically unsaturated compounds consisting of one or more acrylate-functional oligomers dissolved or dispersed in a liquid ethylenically unsaturated diluent and a photoinitiator prior to curing. The coating composition is typically applied to an optical fiber in liquid form and then cured by exposure to actinic radiation.

[0010] The primary coating preferably has a higher refractive index than the cladding of the associated optical fiber to allow for removal of erroneous optical signals from the core of the optical fiber. The primary coating should maintain sufficient adhesion to the glass fiber during thermal and hydrolytic aging, but can be peeled off from the glass fiber for splicing purposes (if necessary). Primary coatings typically have a thickness in the range of 20-50 μm (e.g., about 25 or 32.5 μm), with thinner thicknesses in the range of 15-25 μm for 200 μm fibers.

[0011] The primary coating typically has a thickness of less than about 40 μm, although other thicknesses can be used. The primary coating is typically applied to the glass fiber and then cured. Various additives may also be present that enhance one or more properties of the primary coating, including antioxidants, adhesion promoters, inhibitors, photosensitizers, carrier surfactants, tackifiers, catalysts, stabilizers, surfactants, and optical brighteners.

[0012] The secondary coating is an outer coating. The secondary coating is, for example, a polymerization product of a coating composition in which the molecules are highly crosslinked upon polymerization. The secondary coating typically has a high in situ modulus (e.g., greater than about 800 MPa at 25° C., more preferably between about 1 GPa and about 3 GPa) and a high T g (e.g., greater than about 50° C.). The in situ secondary modulus is preferably greater than about 1000 MPa. The secondary coating often has a thickness of less than about 40 μm.

[0013] Optical fiber coatings, including primary and secondary layers, are typically applied using one of two processes: wet-on-wet (WOW) and wet-on-dry (WOD). In the WOD process, the fiber first passes through a primary coating application, which is cured by exposure to ultraviolet (UV) radiation. The fiber then passes through a secondary coating application, which is subsequently cured by similar means. In the WOW process, once the fiber has passed through both the primary and secondary coating applications, the fiber proceeds to the curing step. In the wet-on-wet process, the curing lamps between the primary and secondary coating applications are omitted.

[0014] Radiant light energy is used to produce radiation-curable coatings for optical fibers. In particular, the curing process uses radiant energy from UV lamps to cure the optical fiber coating. Broadband mercury spectrum UV lamps are commonly used in the industry due to their high intensity and broad emission spectrum that ensures rapid and complete curing of such radiation-curable coatings. Curing systems utilizing UV-LED (light emitting diode) lamps are also increasingly being used as their efficient construction allows for the fiber manufacturing process with less energy input.

[0015] The global demand for optical fiber continues to increase year by year. To meet this growing demand and to provide a productivity advantage in such a competitive industry, it would be beneficial, among other things, to increase the speed at which optical fiber is formed, coated, and cured. With current coating and process technology, most fiber manufacturers can comfortably operate their draw towers at line speeds of at least 1000 m / min, with speeds up to 1500 m / min and even 2500 m / min or more possible.

[0016] However, as fiber draw speeds increase, several technical challenges arise in the process that make it more difficult to produce properly coated optical fiber. Among these technical challenges is a decrease in the ability of the UV light source to provide a sufficient dose of radiation to fully cure the primary and secondary coating compositions as the relative cure exposure times decrease. Further challenges include an increased tendency for runout or concentricity errors in the application of the coated fiber, as the vibrations characteristic of faster line speeds can cause physical movements that exceed the tolerances for accurate coating application. Still further challenges include increased attenuation caused by air bubble entrapment, coating delamination, and microbending.

[0017] Many of these challenges are caused or exacerbated by the inability of a newly applied liquid coating to cure quickly enough at faster line speeds to form a coating with sufficient integrity or adhesion (to the glass or to previously applied coating layers). The increased temperatures caused by faster draw speeds further slow the cure rate of known compositions. Although commercially available acrylate-functionalized coatings are designed to cure quickly, coating cure is often still the rate-limiting step for ramping up optical fiber production. Thus, additional solutions are needed to further improve the cure rate of radiation curable optical fiber coatings.

[0018] Attempts to provide optical fiber coatings that are better suited to increasing process demands are known. WO 2018220605 A1, assigned to DSM IP Assets BV, discloses novel coatings using acrylate-functionalized reactive oligomers and acrylate-functionalized reactive diluent monomers that are configured to handle the additional thermal stresses induced by increased line speeds in that the coatings exhibit improved rheological properties.

[0019] Notwithstanding this, there continues to be a need to provide optical fiber coatings, particularly primary coatings, that form a well crosslinked network quickly enough to handle the increasing demands placed on application and post-coating systems to optical fibers at ever increasing line speeds, and that do not necessarily require increased amounts of expensive photosensitizers, photoinitiators, or other specialized additives. There also continues to be a need to provide optical fiber coatings that exhibit fast cure rates, yet impart desirable properties to the cured coatings produced therefrom, particularly having a low modulus that contributes to excellent microbend resistance. [Brief description of the drawings]

[0020] [Figure 1] 1 is a graph showing the relative elastic modulus based on G'max as a function of time for various radiation curable compositions tested herein (Formulations 68, 69, 70, and 73).

[0021] [Diagram 2] 2 is a graph showing the % unsaturation reacted as a function of time for the same radiation curable composition shown in FIG. 1.

[0022] [Diagram 3] 1 illustrates a schematic cross-section of an optical fiber according to embodiments described herein.

[0023] [Figure 4] 4 is a cross-sectional view taken along line AA showing the configuration of one embodiment of the optical fiber of FIG. 3. Summary of the Invention

[0024] Described herein are several aspects and embodiments of the present invention. The first aspect is a reactive diluent monomer component comprising, consisting essentially of, or consisting of (1) a reactive oligomer component comprising at least one reactive oligomer containing a polymerizable group, wherein at least 20%, or at least 30%, of the molar fraction of the polymerizable groups in the reactive oligomer component are methacrylate groups; (2) a reactive diluent monomer component comprising, consisting essentially of, or consisting of a reactive diluent monomer having at least one polymerizable group capable of (co)polymerizing with the polymerizable group of the reactive oligomer component, comprising a monofunctional acrylate monomer, wherein at least 50%, or at least 80%, of the molar fraction of the polymerizable groups in the reactive diluent monomer component are methacrylate groups; or at least 90%, or at least 95%, or at least 98%, or at least 99% of the monomer components are acrylate, acrylamide, N-vinylamide groups, or mixtures thereof; (3) a photoinitiator component; and (4) optionally, an additive component; the reactive oligomer comprises the reaction product of: (a) a polyol compound; (b) a diisocyanate compound; (c) a hydroxyl-functional compound having at least one methacryloyl group; (d) a compound having a hydroxyl group and no polymerizable groups; and (e) optionally, a silane coupling agent.

[0025] According to another embodiment of the first aspect, the reactive oligomer is a reaction product of a polyol, a diisocyanate, and a hydroxyl functional compound having at least one methacryloyl group, and optionally a compound having a hydroxyl group and no polymerizable group. In another further embodiment of the first aspect, the reactive oligomer and / or the reactive oligomer component have a defined molecular weight value, determined either by theoretical molecular weight or by number average molecular weight. In various embodiments of the first aspect, the reactive oligomer can be single endcapped, multi-endcapped, or partially endcapped with hydroxyl groups. The polymerizable group can occur as a polymerizable end group or a polymerizable backbone group, or both. In another further embodiment, the polymerizable group of the reactive oligomer has a defined amount and / or ratio of methacrylate groups and the polymerizable group of the reactive diluent monomer has a defined amount and / or ratio of acrylate groups. In addition, the compound from which the polymerizable group is formed has a defined reactivity ratio.

[0026] A second aspect of the invention is a method for coating an optical fiber comprising providing a glass optical fiber; applying a primary coating composition to a surface of the glass optical fiber; optionally providing UV light in an amount sufficient to at least partially cure said primary coating composition; applying a secondary coating composition to the primary coating composition; exposing the primary coating composition and the secondary coating composition to at least one radiation source capable of emitting ultraviolet radiation to affect curing of said primary coating composition and said secondary coating composition to form a cured primary coating on the surface of the optical fiber and a cured secondary coating on the surface of the cured primary coating; wherein the primary coating composition is a composition according to any of the embodiments of the first aspect of the invention.

[0027] Another embodiment of the second aspect describes an optical fiber coating method in which the primary coating composition is applied to a surface of a glass optical fiber at a draw speed of greater than 1500 m / min, or greater than 1700 m / min, or greater than 2000 m / min, or greater than 2500 m / min, or greater than 3000 m / min, and less than 5000 m / min, or less than 4000 m / min, or less than 3100 m / min.

[0028] A third aspect of the invention is a coated optical fiber comprising a glass core, a cladding layer in contact with and surrounding the glass core, and a coating portion further comprising a primary coating layer in contact with and surrounding the cladding layer, and a secondary coating layer in contact with and surrounding the primary coating layer. According to this third aspect, the primary coating layer is the cured product of a radiation curable composition according to any of the embodiments of the first aspect, and the primary and secondary coatings are applied and cured according to any of the embodiments of the second aspect. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] A first aspect of the present invention provides a reactive oligomer component comprising, consisting essentially of, or consisting of at least one reactive oligomer containing a polymerizable group; a reactive oligomeric component, wherein at least 20%, or at least 30%, of the mole fraction of polymerizable groups in the reactive oligomeric component consists of methacrylate groups; comprising, consisting of, or consisting essentially of a reactive diluent monomer having at least one polymerizable group capable of (co)polymerizing with a polymerizable group of the reactive oligomer component; a reactive diluent monomer component comprising a monofunctional acrylate monomer, a reactive diluent monomer component, wherein at least 50%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99% of the mole fraction of the polymerizable groups of the reactive diluent monomer component are acrylate groups, acrylamide groups, N-vinylamide groups, or mixtures thereof; a photoinitiator component; and In some cases, additive ingredients Including, The reactive oligomer is Polyol compounds; Diisocyanate compounds; a hydroxyl-functional compound having at least one methacryloyl group; A compound having a hydroxyl group and no polymerizable group; and In some cases, silane coupling agents A radiation curable composition for coating optical fiber comprising the reaction product of:

[0030] The radiation curable composition for coating an optical fiber according to the first aspect of the invention comprises a reactive oligomer component, a reactive diluent monomer component, a photoinitiator component, and optionally an additive component. In a preferred embodiment, the radiation curable composition for coating an optical fiber according to the first aspect of the invention consists of a reactive oligomer component, a reactive diluent monomer component, a photoinitiator component, and optionally one or more additives. Such components, described below, may be used in the radiation curable composition according to any of the aspects of the invention, including the composition according to the first aspect, the composition used in the method for coating an optical fiber according to the second aspect, and the composition whose coating is cured, described in connection with the coated optical fiber according to the third aspect.

[0031] [Reactive oligomer component] The radiation curable composition according to the present invention comprises a reactive oligomeric component. As used herein, "reactive" means the ability to form a chemical reaction, preferably a polymerization reaction, with another molecule. Thus, a reactive compound will be said to have at least one reactive or functional group. Such reactive or functional group is preferably a polymerizable group. On the other hand, oligomer is used herein to mean a molecule of intermediate relative molecular weight, the structure of which actually or conceptually comprises a number of units derived from a molecule of lower relative molecular weight. As used herein, a component is considered an oligomer if it further has a number average molecular weight (Mn) of about 1000 g / mol to about 35000 g / mol, as measured by size exclusion chromatography (SEC). In a preferred embodiment, the reactive oligomeric component comprises one or more reactive oligomers having an Mn of 1000 g / mol to 30000 g / mol, or 800 g / mol to 25000 g / mol, or 1000 g / mol to 20000 g / mol.

[0032] In a preferred embodiment, the reactive oligomer component comprises a plurality of individual reactive oligomer molecules. In one embodiment, the reactive oligomer component consists or consists essentially of a plurality of reactive oligomer molecules, where each molecule has the same or substantially the same chemical structure. In an alternative embodiment, the reactive oligomer component consists of a plurality of reactive oligomer molecules having different chemical structures. In one embodiment, the reactive oligomer component consists of two or more different types of reactive oligomers.

[0033] The reactive oligomer component according to the present invention comprises, consists essentially of, or consists of at least one reactive oligomer having at least one polymerizable group. In a preferred embodiment, the reactive oligomer component consists of a reactive oligomer having at least one polymerizable group. The polymerizable group can be of any known type. However, in one embodiment, the polymerizable group can comprise, consist essentially of, or consist of acrylate, methacrylate, acrylamide, or N-vinylamide groups, or any combination thereof. The reactive oligomer is preferably an ethylenically unsaturated polymerizable compound containing one or more reactive olefinic double bonds.

[0034] Polymerizable groups include polymerizable backbone groups or polymerizable end groups and may occur at any feasible point along the length of the reactive oligomer. Polymerizable backbone groups are linear, present along the length of the oligomer or branched therefrom, while polymerizable end groups are polymerizable groups present at the end of the oligomer. Polymerizable groups may occur separately from or directly or indirectly adjacent to other polymerizable groups, such as, for example, a branch or branching pattern at the end of the oligomer. In one embodiment, the polymerizable group comprises, consists essentially of, or consists of polymerizable end groups. In an alternative embodiment, the polymerizable group comprises a mixture of polymerizable end groups and polymerizable backbone groups.

[0035] In a preferred embodiment, the polymerizable group is derived from the reaction product of constituent hydroxy-functional monomers having a reactive moiety such as a methacrylic moiety. In one embodiment, the hydroxy-functional monomers are selected to have a desired reactivity ratio. As used herein, unless otherwise specified, the reactivity ratio is determined from a theoretical monomer mixture of the hydroxy-functional monomers from which the polymerizable group is derived with 2-hydroxyethyl acrylate (CAS number 818-61-1). As is known in the art to which this invention applies, in determining the reactivity ratio, the May-Lewis equation can be used to consider four different reactions that can theoretically occur in a reactive chain and terminate with either of two monomers with known reaction rate constants. The reactivity ratio is then the ratio of the rate constant of addition of the hydroxy-functional monomer from which the polymerizable group is derived to the addition to the selected standard 2-hydroxyethyl acrylate.

[0036] In an embodiment, the compound, which is a hydroxy-functional monomer having a reactive moiety, is copolymerized with 2-hydroxyethyl acrylate (HEA) in a copolymerization step of the compound (R 1 ) is selected such that the self-reactivity ratio of said compound and HEA (R ) is at least 1, or at least 1.1, or at least 1.2, or at least 1.3, or at least 1.4, or at least 1.5, or at least 1.6, or at least 2, or at least 2.9; or between 1 and 3, or between 1 and 2, or between 1.01 and 1.8, or between 1.1 and 1.7, or between 1.2 and 1.6, or between 1.3 and 1.5. Furthermore, the compound may be selected such that the self-reactivity ratio of said compound and HEA (R ) is at least 1, or at least 1.1, or at least 1.2, or at least 1.3, or at least 1.4, or at least 1.5, or at least 1.6, or at least 2, or at least 2.9; or between 1 and 3, or between 1 and 2, or between 1.01 and 1.8, or between 1.1 and 1.7, or between 1.2 and 1.6, or between 1.3 and 1.5 in the same copolymerization with HEA. 2 ) is selected to have a reactivity ratio of 0.1 to 0.5, or 0.1 to 0.4, or about 0.15 to about 0.35. 1 / R 2 can be, for example, from 3 to 15, or from 3 to 12, or from 3 to 11, or from 4 to 15, or from 4 to 10, or from 5 to 12. In such embodiments, R 1 and R 2can be determined according to a multivariate analysis using infrared spectra of the copolymer input compounds. In a preferred embodiment, the compound that is a hydroxy-functional monomer having a reactive moiety has at least one methacryloyl group.

[0037] The reactivity ratios of many hydroxy-functional monomers are well known in the art and a large list can be found in J. Brandrup, E, H, Immergut, EA Grulke (eds.), Polymer Handbook. Currently, one of the best empirical methods for determining reactivity ratios is by pulsed laser polymerization-size exclusion chromatography-mass spectrometry (PLP-SEC-MS) method, using either electrospray or matrix-assisted laser desorption / ionization (MALDI-TOF) as the MS method. For compounds with separable IR signals, the method described in Jansen et al.: Real-Time Infrared Determination of Photoinitiated Copolymerization Reactivity Ratios: Application of the Hilbert Transform and Critical Evaluation of Data Analysis Techniques; Macromolecules 2004, 37, 2275-2286 (2004) is also considered suitable, as it is a sufficient mimic of the UV polymerization process. The nature of the RT-FTIR analysis performed is multivariate, and it is preferable to combine it with NLLS methodology for reactivity ratio analysis.

[0038] The reactive oligomer according to the present invention may be of any known type consistent with the definitions set forth elsewhere herein. However, in a preferred embodiment, the reactive oligomer component comprises, consists essentially of, or consists of one or more urethane-based reactive oligomers. The urethane-based reactive oligomers, also referred to herein as "reactive urethane oligomers", preferably comprise a backbone, a urethane group, and a polymerizable group. In a preferred embodiment, the urethane-based oligomer comprises a urethane methacrylate oligomer. The urethane methacrylate oligomer is preferably a reaction product of a polyol compound, a diisocyanate compound, and a hydroxyl group-containing methacrylate compound.

[0039] Examples of suitable polyol compounds include polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, acrylic polyols, and other polyols. These polyols can be used individually or in combination of two or more. In a preferred embodiment, the backbone of the urethane-based reactive oligomer includes a compound derived from polypropylene glycol (PPG). As used herein, a compound derived from polypropylene glycol includes end-capped PPG, such as PPG end-capped with EO. There is no particular restriction on the polymerization method of the structural units of these polyols. Random polymerization, block polymerization, or graft polymerization are each acceptable.

[0040] As used herein, block copolymer refers to a portion of an oligomer or polymer that contains many constitutional units, and includes the characteristic that at least one constitutional unit is not present in the adjacent portion. As used herein, mono-, di-, and triblock copolymers refer to the average amount of a particular block present in the oligomer. In a preferred embodiment, the particular block refers to a polyether block derived from one or more polyols, preferably polyether polyols, as described elsewhere herein. In one embodiment, the blocks to which mono-, di-, and / or triblock copolymers refer are polyether blocks derived from one or more polyols as described elsewhere herein. In one embodiment, a monoblock copolymer may be described as a copolymer having only about 1, or about 0.9 to less than 1.5 units, on average, of a particular block, such as a polyether block. In one embodiment, a diblock copolymer may be described as a copolymer having only about 2, or at least 1.5 to less than 2.5 units, on average, of a particular block, such as a polyether block. In one embodiment, a triblock copolymer may be described as a copolymer having only about 3, or about 2.5 to less than 3.5 units, on average, of a particular block, such as a polyether block. The number of polyether units in a given oligomer may be determined by the number of polyether polyol molecules utilized in the synthesis of a single oligomer.

[0041] Examples of polyether polyols include polyethylene glycol, polypropylene glycol, polypropylene glycol-ethylene glycol copolymer, polytetramethylene glycol, polyhexamethylene glycol, polyheptamethylene glycol, polydecamethylene glycol, and polyether diols obtained by ring-opening copolymerization of two or more ionically polymerizable cyclic compounds. Examples of the ionically polymerizable cyclic compounds include cyclic ethers such as ethylene oxide, isobutene oxide, tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, dioxane, trioxane, tetraoxane, cyclohexene oxide, styrene oxide, epichlorohydrin, isoprene monoxide, vinyl oxetane, vinyltetrahydrofuran, vinylcyclohexene oxide, phenyl glycidyl ether, butyl glycidyl ether, and glycidyl benzoate. Specific examples of combinations of two or more ionically polymerizable cyclic compounds include combinations for producing binary copolymers such as tetrahydrofuran and 2-methyltetrahydrofuran, tetrahydrofuran and 3-methyltetrahydrofuran, and tetrahydrofuran and ethylene oxide; and combinations for producing ternary copolymers such as combinations of tetrahydrofuran, 2-methyltetrahydrofuran, and ethylene oxide, combinations of tetrahydrofuran, butene-1-oxide, and ethylene oxide, etc. The ring-opened copolymers of these ionically polymerizable cyclic compounds can be either random copolymers or block copolymers.

[0042] Included among these polyether polyols are, for example, products sold under the trademarks PTMG1000, PTMG2000 (manufactured by Mitsubishi Chemical Corporation), PEG#1000 (manufactured by NOF Corporation), PTG650(SN), PTG1000(SN), PTG2000(SN), PTG3000, PTGL1000, PTGL2000 (manufactured by Hodogaya Chemical Co., Ltd.), PEG400, PEG600, PEG1000, PEG1500, PEG2000, PEG4000, PEG6000 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and Pluronics (manufactured by BASF).

[0043] An example of the polyester polyol is a polyester diol obtained by reacting a polyhydric alcohol with a polybasic acid. Examples of the polyhydric alcohol include ethylene glycol, polyethylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, and 2-methyl-1,8-octanediol. Examples of the polybasic acid include phthalic acid, dimer acid, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, adipic acid, and sebacic acid.

[0044] These polyester polyol compounds are commercially available under trademarks such as MPD / IPA500, MPD / IPA1000, MPD / IPA2000, MPD / TPA500, MPD / TPA1000, MPD / TPA2000, Kurapol A-1010, A-2010, PNA-2000, PNOA-1010, and PNOA-2010 (manufactured by Kuraray Co., Ltd.).

[0045] Examples of polycarbonate polyols include, but are not limited to, polycarbonate of polytetrahydrofuran, poly(hexanediol carbonate), poly(nonanediol carbonate), poly(3-methyl-1,5-pentamethylene carbonate), and the like.

[0046] Commercially available polycarbonate polyols include, but are not limited to, DN-980, DN-981 (manufactured by Nippon Polyurethane Industry Co., Ltd.), Priplast 3196, 3190, 2033 (manufactured by Unichema), PNOC-2000, PNOC-1000 (manufactured by Kuraray Co., Ltd.), PLACCEL CD220, CD210, CD208, CD205 (manufactured by Daicel Chemical Industries, Ltd.), PC-THF-CD (manufactured by BASF), and the like.

[0047] On the other hand, polycaprolactone diol is obtained by reacting e-caprolactone with a diol compound. In one embodiment, the polycaprolactone polyol has a melting point of 0° C. or higher. Examples of the diol compound include ethylene glycol, polyethylene glycol, polypropylene glycol, tetramethylene glycol, polytetramethylene glycol, 1,2-polybutylene glycol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and 1,4-butanediol.

[0048] Commercially available products of these polycaprolactone polyols include PLACCEL 240, 230, 230ST, 220, 220ST, 220NP1, 212, 210, 220N, 210N, L230AL, L220AL, L220PL, L220PM, L212AL (all manufactured by Daicel Chemical Industries, Ltd.), Rauccarb 107 (manufactured by Enichem), and the like.

[0049] Examples of other polyols include ethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, polyoxyethylene bisphenol A ether, polyoxypropylene bisphenol A ether, polyoxyethylene bisphenol F ether, polyoxypropylene bisphenol F ether, and the like.

[0050] As these other polyols, those having an alkylene oxide structure in the molecule, particularly polyether polyols, are preferred. In one embodiment, polyols containing polytetramethylene glycol and copolymer glycols of butylene oxide and ethylene oxide are preferred.

[0051] The number average molecular weight, derived from the hydroxyl number of these polyols, is typically from about 50 to about 15000, preferably from about 1000 to about 8000. As used herein, unless otherwise specified, molecular weight refers to the number average molecular weight specified in grams per mole (g / mol) as determined by the SEC method.

[0052] The urethane-based reactive oligomer is also preferably a reaction product of a polyisocyanate compound, preferably a diisocyanate compound. Examples of suitable diisocyanates include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, (hydrogenated) xylylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 3,3'-dimethylphenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1,6-hexane diisocyanate, isophorone diisocyanate, methylenebis(4-cyclohexylisocyanate), 1,6-hexane diisocyanate, ... bis(2-isocyanato-ethyl) fumarate, 6-isopropyl-1,3-phenyl diisocyanate, 4-diphenylpropane diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, tetramethylxylylene diisocyanate, lysine isocyanate, and the like.

[0053] These diisocyanate compounds can be used individually or in combination of two or more. Preferred diisocyanates are isophorone diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4 trimethylhexamethylene diisocyanate and hexamethylene diisocyanate, 2,4-tolylene diisocyanate, and 2,6-tolylene diisocyanate.

[0054] Urethane-based reactive oligomer is also preferably a reaction product of hydroxyl group-containing (meth)acrylate compound.Examples of hydroxyl group-containing (meth)acrylate used include (meth)acrylate derived from (meth)acrylic acid and epoxy, and (meth)acrylate containing alkylene oxide, more specifically, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl acrylate, 2-hydroxy-3-oxyphenyl (meth)acrylate, and hydroxyethyl caprolactone acrylate.As described below, methacrylate compound is strongly preferred.

[0055] Surprisingly, the inventors have now discovered that compositions containing methacrylate functionality, when defined as discussed elsewhere herein and claimed, exhibit superior application-specific properties. More specifically, the inventors have now unexpectedly discovered that compositions according to the present invention, when the reactive oligomer component contains a specific amount of methacrylate-functional polymerizable groups, form faster viable optical fiber coatings than those derived from traditionally defined all-acrylate systems. Moreover, it has now been observed that such coating compositions achieve this while also promoting the formation of cured optical fiber coatings having an ultimate modulus comparable to or even lower than traditional all-acrylate analogs. It has now been observed that this is so even though such coatings are slower curing, as measured by percent reacted unsaturation (%RAU) compared to equivalent all-acrylate compositions. Indeed, these results are truly surprising, considering that it is well established that systems containing acrylic unsaturation are significantly more reactive than those containing methacrylic double bonds (see, for example, Radiation Curing in Polymer Science and Technology - Vol. 1: Fundamentals and Methods, I. Fouassier, JP et al., Elsevier Science Publishers Ltd. 1993 pp. 8-9), and further that methacrylic unsaturated products are known to be harder and less flexible than comparable acrylic products (ibid.).

[0056] Thus, the inventors have surprisingly discovered that compositions containing methacrylate-functional reactive oligomers, while not necessarily curing faster in the traditional %RAU metric, nevertheless build up a sufficiently high network modulus faster than compositions containing reactive oligomers with exclusively acrylate-functional reactive oligomers. This makes such compositions more suitable for high speed applications in optical fiber coating applications where high line speeds and proximity to the next manufacturing operation (application of a secondary coating or spooling of freshly coated optical fiber) govern the build up of high speed network properties where they are paramount. The inventors' insight to study cure rate performance in a manner beyond the traditionally relied upon %RAU methodology facilitated the discovery of the present superior performance combinations that have been previously overlooked despite decades of previous optical fiber coating development.

[0057] Thus, at least some of the polymerizable groups of the reactive oligomers in the reactive oligomer component contain methacrylic double bonds. In a preferred embodiment, the polymerizable groups of the reactive oligomers contain methacrylate groups. In a preferred embodiment, at least 10%, or at least 20%, or at least 30%, or at least 33%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 99%, or about 100% of the polymerizable groups of the reactive oligomer component consist of methacrylate groups. In preferred embodiments, the ratio of methacrylate groups to acrylate groups present in all reactive oligomers of the reactive oligomer component is greater than 1:9, or greater than 1:4, or greater than 1:3, or greater than 1:2, or greater than 1:1, or greater than 3:2, or greater than 2:1, or greater than 3:1, or greater than 5:1, or greater than 8:1, or greater than 9:1, or greater than 100:1.

[0058] In one embodiment, the polymerizable groups present in the reactive oligomer component consist essentially of or consist of methacrylate groups. In another embodiment, the reactive oligomer component consists essentially of or consists of methacrylate groups, when counting only the total number of methacrylate and acrylate groups present in all reactive oligomers as polymerizable groups.

[0059] On the other hand, with respect to the entire composition, in preferred embodiments, the molar percentage of methacrylate groups present in the composition of the total amount of polymerizable groups present in the reactive oligomer component and the reactive diluent monomer component is from 1% to 20%, or from 1% to 18%, or from 1% to 15%, or from 2% to 20%, or from 2% to 18%, or from 2% to 15%, or from 4% to 20%, or from 4% to 18%, or from 4% to 15%, or from 9% to 20%, or from 9% to 18%, or from 9% to 15%. In another embodiment, the molar ratio of methacrylate groups to (meth)acrylate groups (i.e. all methacrylate groups and all acrylate groups) is from 2% to 20%, or from 2% to 18%, or from 2% to 15%, or from 4% to 20%, or from 4% to 18%, or from 4% to 15%, or from 9% to 20%, or from 9% to 18%, or from 9% to 15%.

[0060] Various ratios of compounds used to synthesize reactive oligomers in reactive oligomer components can be used. For urethane-based reactive oligomers, in one embodiment, the ratios of polyol, diisocyanate, and hydroxyl group-containing (meth)acrylate used to prepare urethane (meth)acrylate reactive oligomers are determined so that about 1.1 to about 3 equivalents of isocyanate groups contained in diisocyanate and about 0.1 to about 1.5 equivalents of hydroxyl groups contained in hydroxyl group-containing (meth)acrylate are used per equivalent of hydroxyl groups contained in polyol.

[0061] In the reaction of the three components used to prepare the urethane-based reactive oligomer, a urethanization catalyst is also preferably used. Such catalysts include, by way of example, copper naphthenate, cobalt naphthenate, zinc naphthenate, di-n-butyltin dilaurate, triethylamine, and triethylenediamine-2-methyltriethyleneamine. The catalyst can be used in any suitable amount, or, for example, from about 0.01 to about 1% by weight of the total amount of reactants. The reaction can be carried out at any suitable temperature, such as a temperature of about 10 to about 90°C, preferably about 30 to about 80°C.

[0062] The reactive oligomer component may also include one or more urethane-free reactive oligomers. Examples of urethane-free reactive oligomers include (meth)acrylated acrylic oligomers, urethane-free polyester (meth)acrylate oligomers, and urethane-free alkyd (meth)acrylate oligomers. Other such oligomers that may be used include polyester (meth)acrylate oligomers, epoxy (meth)acrylate oligomers, polyamide (meth)acrylate oligomers, siloxane oligomers with (meth)acryloyloxy groups, and reactive oligomers obtained by reacting (meth)acrylic acid with copolymers of glycidyl methacrylate and other polymerizable monomers. Further examples of reactive oligomers include unsaturated polyester resins, which are usually prepared from maleic acid, phthalic acid, and one or more diols, and have a molecular weight of more than about 500. This type of unsaturated oligomer is also known as a prepolymer. Typical examples of unsaturated compounds are esters of ethylenically unsaturated carboxylic acids with polyols or polyepoxides, and polymers containing ethylenically unsaturated groups in the chain or in the side chain, such as unsaturated polyesters, polyamides and their copolymers, polybutadiene and butadiene copolymers, polyisoprene and isoprene copolymers, polymers and copolymers containing (meth)acrylic groups in the side chain, and mixtures of one or more such polymers.

[0063] Illustrative examples of unsaturated carboxylic acids are unsaturated fatty acids such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, cinnamic acid, linoleic acid or oleic acid. Suitable polyols are aromatic, aliphatic and cycloaliphatic polyols. Aromatic polyols are typically hydroquinone, 4,4'-dihydroxydiphenyl, 2,2-bis(4-hydroxyphenyl)propane, as well as novolaks and cresols. Polyepoxides include those based on the cited polyols, such as aromatic polyols and epichlorohydrin.

[0064] In one embodiment, the reactive oligomer component includes one or more bisphenol A based (meth)acrylate oligomers, such as alkoxylated bisphenol-A-di(meth)acrylate and diglycidyl-bisphenol-A-di(meth)acrylate, hi another embodiment, the reactive oligomer component comprises, consists essentially of, or consists of polyether based methacrylate oligomers, polycarbonate methacrylate oligomers, polyester methacrylate oligomers, alkyd methacrylate oligomers, and methacrylated acrylic oligomers, and mixtures thereof.

[0065] In a preferred embodiment, the reactive oligomer component comprises, consists essentially of, or consists of one or more difunctional oligomers. As used herein, "difunctional" means having an average of 1.5 to less than 2.5 polymerizable groups per molecule, as determined by NMR methods. However, in other embodiments, the reactive oligomer component comprises, consists essentially of, or consists of at least oligomers having a functionality greater than 2.5, such as in the situation where a difunctional end capper is placed at the end of the oligomer. Thus, in one embodiment, the reactive oligomer component comprises, consists essentially of, or consists of trifunctional (i.e., 2.5 to 3.4 polymerizable groups per molecule) or tetrafunctional (i.e., 3.5 to 4.4 polymerizable groups per molecule) oligomers.

[0066] Furthermore, in a preferred embodiment, the reactive oligomer component comprises, consists essentially of, or consists of one or more reactive oligomers having a Mn greater than 2000 g / mol. If the Mn of any (or all) of the reactive oligomers is below this value, the final coating properties may be adversely affected and / or the composition may tend to solidify at room temperature. In one embodiment, the reactive oligomer component has an even higher Mn, for example, greater than 3000, or greater than 4000, or greater than 5000, or greater than 6000, or greater than 7000, or greater than 8000 g / mol.

[0067] In a preferred embodiment, the reactive oligomer component comprises, consists essentially of, or consists of difunctional urethane-containing reactive oligomers having Mn of 7000 g / mol to 25000 g / mol. In a preferred embodiment, such oligomers are aliphatic polyether urethane methacrylate oligomers and aliphatic urethane methacrylate oligomers using blends of the above polyols. The term "aliphatic" as used herein with respect to the reactive oligomers refers to the fact that entirely aliphatic diisocyanates are used.

[0068] Any suitable amount of one or more of the reactive oligomers listed above may be used in the compositions of the present invention, and may be selected alone or in combination with one or more of the types listed herein. In one embodiment, the reactive oligomer component is present in an amount of about 5% to about 90%, or about 10% to about 90%, or about 10% to about 80% by weight, based on the total weight of the composition. In one embodiment, the reactive oligomer component is present in an amount of at least 30%, or at least 40%, or at least 50%, or at least 55%, or at least 60%, or at least 65%, or at least 70%, or 25-90%, or 30-85%, or 40-80%, or 45-85%, or 55-80%, or 60-85%, or 60-80% by weight.

[0069] [Reactive diluent monomer] The composition according to the first aspect of the invention also includes a reactive diluent monomer component. As specified with respect to the qualification of the oligomer component described elsewhere herein, "reactive" means the ability to form a chemical reaction, preferably a polymerization reaction, with another molecule. Thus, a reactive compound will be said to have at least one reactive or functional group. Such reactive or functional group is preferably a polymerizable group. On the other hand, monomer is used herein to mean a molecule of low relative molecular weight whose structure is capable of undergoing polymerization, thereby providing a building block for the essential structure of a polymer. As used herein, a component is considered to be a monomer if it further has a number average molecular weight (Mn) of less than about 1000 g / mol. However, in a preferred embodiment, the reactive diluent monomer component consists of one or more reactive diluent monomers having an Mn of about 86 g / mol (the molar mass of methyl acrylate) to 800 g / mol, or 100 g / mol to 350 g / mol, as measured by an appropriate SEC method. In another embodiment, the reactive diluent monomer component comprises one or more reactive diluent monomers having a theoretical molecular weight of about 86 g / mol to 800 g / mol, or 100 g / mol to 350 g / mol, where Mn,theo is determined by adding up the standard atomic weights of all atoms in the ideal chemical structure associated with a particular compound. Thus, the Mn,theo of a compound is also commonly referred to as the molar mass of that compound.

[0070] As used herein, "diluent" means a substance that reduces the viscosity of a larger composition to which it is added or with which it is associated. Various diluents are used to maximize the flowability, and therefore the processability, of the optical fiber coating compositions with which they are associated.

[0071] In a preferred embodiment, the reactive diluent monomer component comprises a plurality of individual reactive diluent monomer molecules. In one embodiment, the reactive diluent monomer component consists of or consists essentially of a plurality of reactive diluent monomer molecules, where each molecule has the same or substantially the same chemical structure. In an alternative embodiment, the reactive diluent monomer component consists of a plurality of reactive diluent monomer molecules having different chemical structures. In one embodiment, the reactive diluent monomer component consists of two or more different types of reactive diluent monomers.

[0072] The reactive diluent monomer component according to the present invention comprises, consists essentially of or consists of a reactive diluent monomer having at least one polymerizable group. In a preferred embodiment, the reactive diluent monomer component consists of a reactive diluent monomer having on average one polymerizable group. The polymerizable group of the reactive diluent monomer is preferably capable of (co)polymerizing with a polymerizable group present in the associated reactive oligomer component.

[0073] The polymerizable group of the reactive diluent monomer component can be of any known type. However, in one embodiment, the polymerizable group can comprise, consist essentially of, or consist of an acrylate, an acrylamide, or an N-vinylamide group, or any combination thereof. The reactive diluent monomer is preferably an ethylenically unsaturated polymerizable compound that contains at least one reactive olefinic double bond.

[0074] The polymerizable group may occur at any feasible point along the length of the reactive diluent monomer, however, in preferred embodiments the polymerizable group comprises, consists essentially of, or consists of a polymerizable end group.

[0075] The reactive diluent monomers according to the present invention may be of any known type consistent with the definitions specified elsewhere herein, however, in preferred embodiments, the reactive diluent monomer comprises, consists essentially of, or consists of one or more reactive diluent monomers containing a double bond.

[0076] Typical examples of such reactive diluent monomers containing one double bond are alkyl or hydroxyalkyl acrylates, such as methyl, ethyl, butyl, 2-phenoxyethyl, 2-ethylhexyl, and 2-hydroxyethyl acrylate, isobornyl acrylate, methyl and ethyl acrylate, lauryl acrylate, ethoxylated nonyl-phenol acrylate, and diethylene-glycol-ethyl-hexyl acylate (DEGEHA). Further examples of these monomers are acrylonitrile, acrylamide, N-substituted acrylamide, vinyl esters, such as vinyl acetate, styrene, alkylstyrenes, halostyrenes, N-vinylpyrrolidone, N-vinylcaprolactam, vinyl chloride, and vinylidene chloride. Examples of monomers containing more than one double bond are ethylene glycol diacrylate, propylene glycol diacrylate, tripropylene glycol diacrylate, neopentyl glycol diacrylate, hexamethylene glycol diacrylate, bisphenol A diacrylate, 4,4'-bis(2-acryloyloxyethoxy)diphenylpropane, trimethylolpropane triacrylate, pentaerythritol triacrylate and tetraacrylate, and vinyl acrylate.

[0077] The monomers used can be non-polar or polar. Certain non-polar monomers that may be suitably used include 2-ethylhexyl acrylate (EHA), tridecyl acrylate (TDA), isodecyl acrylate (IDA), lauryl acrylate (LA), isobornyl acrylate (IBOA), and various caprolactone acrylates, such as Tone TM Such as those commercially known as M100 or Sartomer SR495B.

[0078] More polar monomers that can be used include dimethylacrylamide (dMAA), N-vinylpyrrolidone (nVP), 2-(2-ethoxyethoxy)ethyl acrylate (EOEOA), 4-hydroxybutyl acrylate (4-HBA), 2-phenoxyethyl acrylate (PEA), ethoxylated nonylphenol acrylate (ENPA), ethoxylated 2-phenoxyethyl acrylate (EPEA), and propoxylated nonylphenol acrylate (PONPA).

[0079] As discussed above, the inventors have now unexpectedly discovered that compositions incorporating reactive oligomers having methacrylate functionality, as described above, facilitate the formation of superior application-specific properties. However, it has now been further discovered that such properties are achievable when such methacrylate-functional oligomers are paired with certain types of reactive diluent monomers. Specifically, the inventors have surprisingly discovered that these superior results are obtained when methacrylate-functional oligomers are paired with reactive diluent monomers having at least some non-methacrylate functionality, such as diluent monomers having acrylate, acrylamide, or N-vinylamide functionality.

[0080] Thus, at least some of the polymerizable groups of the reactive diluent monomers in the reactive diluent monomer component contain acrylic or N-vinyl double bonds. In preferred embodiments, the polymerizable groups of the reactive diluent monomers comprise acrylate, acrylamide, or N-vinylamide groups. In preferred embodiments, at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 99%, or about 100% of the polymerizable groups of the reactive diluent monomer component consist of one or more acrylate, acrylamide, and / or N-vinylamide groups.

[0081] In an alternative embodiment, the polymerizable groups present in the reactive diluent monomer component consist essentially of acrylate groups. In another embodiment, the reactive diluent monomer component consists essentially of acrylate groups when counting only the total number of methacrylate and acrylate groups present as polymerizable groups in all of the reactive diluent monomers in the reactive diluent monomer component.

[0082] In preferred embodiments, at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90%, or at least 99%, or about 100% of the polymerizable groups of the reactive diluent monomer component consist of one or more acrylate groups. In preferred embodiments, the polymerizable groups or polymerizable end groups of the reactive diluent monomer component consist of, or consist essentially of, acrylate groups. Furthermore, it is preferred to keep the number of methacrylate groups in the reactive diluent monomer component as low as possible, preferably less than 20%, or less than 10%, or less than 5%, or less than 1%, or preferably about 0%, of the total number of polymerizable groups in the reactive diluent monomer component.

[0083] However, with respect to the total composition, in one embodiment the ratio of acrylate groups to methacrylate groups present in the total composition is greater than 4:1, or greater than 25:1, but preferably less than 50:1. Alternatively, the ratio of acrylate groups to methacrylate groups present in the total composition is from 4:1 to 50:1, or from 4:1 to 25:1, or from 4:1 to 10:1, or from 4.6:1 to 50:1, or from 4.6:1 to 25:1, or from 4.6:1 to 10:1, or from 5.6:1 to 50:1, or from 5.6:1 to 25:1, or from 5.6:1 to 10:1.

[0084] In a preferred embodiment, the reactive diluent monomer component comprises, consists essentially of, or consists of one or more monofunctional diluent monomers. As used herein, "monofunctional" means having an average of between 0.5 and 1.4 polymerizable groups per molecule, as determined by nuclear magnetic resonance spectroscopy (NMR) methods.

[0085] One or more of the aforementioned reactive diluent monomers may be used in the compositions of the present invention in any suitable amount and may be selected alone or in combination with one or more of the types listed herein to adjust the viscosity of the formulations to which they relate, making them suitable for the optical fiber coating process with which they are used according to methods well known in the art to which the present invention applies. In one embodiment, the reactive diluent monomer component is present in an amount of 1% to 50% by weight, or 1% to 30% by weight, or 5% to 70% by weight, or 5% to 50% by weight, or 10% to 70% by weight, or 10% to 60% by weight, or 10% to 50% by weight, or 20% to 50% by weight, based on the total weight of the radiation curable composition.

[0086] [Photoinitiator component] In a preferred embodiment, the liquid radiation curable resin for coating optical fibers of the present invention includes a photoinitiator component. A photoinitiator is a compound that is chemically altered by the action of light or a synergistic effect between the action of light and the electronic excitation of a sensitizing dye to produce at least one of a radical, an acid, and a base. Well-known types of photoinitiators include cationic photoinitiators and free radical photoinitiators. According to one embodiment of the present invention, the photoinitiator is a free radical photoinitiator.

[0087] In one embodiment, the photoinitiator comprises an acylphosphine oxide photoinitiator, as disclosed, for example, in U.S. Patent Nos. 4,324,744, 4,737,593, 5,942,290, 5,534,559, 6,020,529, 6,486,228, and 6,486,226.

[0088] The acylphosphine oxide photoinitiator is a bisacylphosphine oxide (BAPO) or a monoacylphosphine oxide (MAPO).

[0089] The bisacylphosphine oxide photoinitiator is of formula I: JPEG0007618588000001.jpg39168In the above formula, R 50 is unsubstituted or is 1 to 4 halogen or C 1 -C 8 Alkyl-substituted, C 1 -C 12 alkyl, cyclohexyl or phenyl; R 51 and R 52 are C 1 -C 8 Alkyl or C 1 -C 8 is alkoxy; R 53 is hydrogen or C 1 -C 8 is alkyl; and R 54 is hydrogen or methyl.

[0090] For example, R 50 is unsubstituted or has 1 to 4 C 1 -C 4 Alkyl, Cl or Br substituted, C 2 -C 10 alkyl, cyclohexyl or phenyl. Another embodiment is R 50 is unsubstituted or at the 2-, 3-, 4- or 2,5-positions is C 1 -C 4 Alkyl-substituted C 3 -C 8 For example, R 50 is C 4 -C 12 alkyl or cyclohexyl; R 51 and R 52 are C 1 -C 8 Alkyl or C 1 -C 8 Alkoxy, R 53 is hydrogen or C 1 -C 8 For example, R 51 and R 52 is C1 -C 4 Alkyl or C 1 -C 4 Alkoxy, R 53 is hydrogen or C 1 -C 4 Another embodiment is R 51 and R 52 is methyl or methoxy, R 53 is hydrogen or methyl. For example, R 51 , R 52 , and R 53 is methyl. Another embodiment is 51 , R 52 , and R 53 is methyl and R 54 Another embodiment is when R 50 C 3 -C 8 For example, R 51 and R 52 is methoxy, R 53 and R 54 is hydrogen, R 50 is isooctyl. For example, R 50 is isobutyl. For example, R 50 is phenyl. The bisacylphosphine oxide photoinitiator is, for example, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (CAS#162881-26-7) or bis(2,4,6-trimethylbenzoyl)-(2,4-bis-pentyloxyphenyl)phosphine oxide.

[0091] The monoacylphosphine oxide photoinitiator is of formula II: JPEG0007618588000002.jpg31161In the above formula, R 1 and R 2 are, independently of each other, unsubstituted or halogen, C 1 -C 8 Alkyl and / or C 1 -C 8 substituted 1 to 4 times with alkoxy, C 1 -C12 alkyl, benzyl, phenyl, or cyclohexyl or the group -COR 3 or R 1 -OR 4 and; R 3 is unsubstituted or C 1 -C 8 Alkyl, C 1 -C 8 Alkoxy, C 1 -C 8 phenyl substituted one to four times by alkylthio and / or halogen; and R 4 is C 1 -C 8 alkyl, phenyl or benzyl. For example, R 1 -OR 4 For example, R 2 is unsubstituted or halogen, C 1 -C 8 Alkyl and / or C 1 -C 8 phenyl substituted 1 to 4 times with alkoxy. For example, R 3 is unsubstituted or C 1 -C 8 Phenyl substituted 1 to 4 times with alkyl. For example, the monoacylphosphine oxide is 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (CAS#84434-11-7) or 2,4,6-trimethylbenzoyldiphenylphosphine oxide (CAS#12790-72-6).

[0092] The compositions according to the invention may also use further photoinitiators, for example α-hydroxyketone photoinitiators of formula III: JPEG0007618588000003.jpg26157In the above formula R 11 and R 12 are independently hydrogen, C 1 -C 6 Alkyl, Phenyl, C 1 -C6 Alkoxy, OSiR 16 (R 17 ) 2 or -O(CH 2 CH 2 O) q -C 1 -C 6 is alkyl, or R 11 and R 12 together with the carbon atom to which they are attached form a cyclohexyl ring; q is a number between 1 and 20; R 13 OH, C 1 -C 16 Alkoxy or -O(CH 2 CH 2 O) q -C 1 -C 6 is alkyl; R 14 is hydrogen, C 1 -C 18 Alkyl, C 1 -C 12 Hydroxyalkyl, C 1 -C 18 Alkoxy, -OCH 2 CH 2 -OR 15 , -CH=CH 2 , -C(CH 3 )=CH 2 or JPEG0007618588000004.jpg78161, n is a number from 2 to 10; R 15 is hydrogen, -COCH=CH 2 or -COC(CH 3 )=CH 2 and; R 16 and R 17 are independent of each other, C 1 -C 8 alkyl or phenyl; and G 3 and G 4are each independently an end group of the polymer structure, preferably hydrogen or methyl.

[0093] The α-hydroxyketone photoinitiators of interest are R 11 and R 12 are independently hydrogen, C 1 -C 6 alkyl or phenyl, or R 11 and R 12 form a cyclohexyl ring together with the carbon atom to which they are attached, and R 13 is OH and R 14 is hydrogen, C 1 -C 12 Alkyl, C 1 -C 12 Alkoxy, -OCH 2 CH 2 OR 15 , -C(CH 3 )=CH 2 or The image is JPEG0007618588000005.jpg99170.

[0094] For example, suitable α-hydroxyketone photoinitiators include R 11 and R 12 are each independently methyl or ethyl, or R 11 and R 12 form a cyclohexyl ring together with the carbon atom to which they are attached, and R 13 is hydrogen and R 14 is hydrogen, C 1 -C 4 Alkyl, C 1 -C 4 Alkoxy or -OCH 2 CH 2 Also of interest are those in which R 14 but The compound is JPEG0007618588000006.jpg19158.

[0095] For example, suitable α-hydroxyketone photoinitiators include α-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropanone, 2-hydroxy-2-methyl-1-(4-isopropylphenyl)propanone, 2-hydroxy-2-methyl-1-(4-dodecylphenyl)propanone, 2-Hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]-phenyl}-2-methyl-propan-1-one and 2-Hydroxy-2-methyl-1-[(2-hydroxyethoxy)phenyl]propanone It is.

[0096] The α-hydroxyketone photoinitiator is, for example, α-hydroxycyclohexyl phenyl ketone or 2-hydroxy-2-methyl-1-phenyl-1-propanone. The linear or branched alkyl is, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, isooctyl, hexyl, heptyl, octyl, nonyl, decyl or dodecyl. Similarly, the alkoxy or alkylthio is of the same linear or branched chain.

[0097] The photoinitiators of the present invention can be used alone or in combination as a blend of one or more. Suitable photoinitiator blends are disclosed, for example, in US Patent No. 6,020,528 and US Patent Application No. 60 / 498,848. According to one embodiment, the photoinitiator component comprises a photoinitiator blend of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (CAS#162881-26-7) and 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide (CAS#84434-11-7) in a weight ratio of, for example, about 1:11, 1:10, 1:9, 1:8, or 1:7.

[0098] Another particularly suitable photoinitiator blend is a mixture of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide and 2-hydroxy-2-methyl-1-phenyl-1-propanone (CAS#7473-98-5), for example in a weight ratio of about 3:1:15 or 3:1:16 or 4:1:15 or 4:1:16. Another suitable photoinitiator blend is a mixture of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2-hydroxy-2-methyl-1-phenyl-1-propanone, for example in a weight ratio of about 1:3, 1:4 or 1:5. In one embodiment, the acylphosphine oxide or photoinitiator blend is present in the radiation curable composition at about 0.2 to about 10% by weight, based on the weight of the composition. For example, the photoinitiator blend is present at about 0.5 to about 8 weight percent, about 1 to about 7 weight percent, or about 2, 3, 4, 5, or 6 weight percent based on the weight of the radiation curable composition.

[0099] Other suitable photoinitiators according to the invention are, for example, other mono- or bisacylphosphine oxides, such as diphenyl-2,4,6-trimethylbenzoylphosphine oxide or bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; α-hydroxyketones, such as 1-hydroxycyclohexyl phenyl ketone or 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone; α-aminoketones, such as 1-hydroxycyclohexyl phenyl ketone or 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone; benzophenones, such as 2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-(4-methylbenzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone or 2-benzyl-2-(dimethylamino)-1-[3,4-dimethoxyphenyl]-1-butanone; Phenone, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone, 2-methylbenzophenone, 2-methoxycarbonylbenzophenone, 4,4'-bis(chloromethyl)-benzophenone, 4-chlorobenzophenone, 4-phenylbenzophenone, 4,4'-bis(dimethylamino)-benzophenone, 4,4'-bis(diethylamino)benzophenone, methyl 2-benzoylbenzoate, 3,3'-dimethyl-4-methoxybenzophenone, 4 -(4-methylphenylthio)benzophenone, 2,4,6-trimethyl-4'-phenyl-benzophenone or 3-methyl-4'-phenyl-benzophenone; ketal compounds such as 2,2-dimethoxy-1,2-diphenyl-ethanone; and monomeric or dimeric phenylglyoxylates such as methylphenylglyoxylate, 5,5'-oxo-di(ethyleneoxydicarbonylphenyl) or 1,2-(benzoylcarboxy)ethane.

[0100] Other suitable photoinitiators for use in accordance with the present invention, with or without an acylphosphine oxide photoinitiator, are oxime esters, such as those disclosed in U.S. Pat. No. 6,596,445. Suitable oxime ester photoinitiators include, for example, JPEG0007618588000007.jpg19150.

[0101] Another class of suitable photoinitiators according to the present invention, with or without an acylphosphine oxide photoinitiator, are, for example, phenylglyoxalates, as disclosed, for example, in U.S. Pat. No. 6,048,660, such as those of the formula: JPEG0007618588000008.jpg24151, where Y is C 1 -C 12 Alkylene, cyclohexylene, cyclohexylene, O, S, or NR 30 C interrupted one or more times by 2 -C 40 alkylene, R 30 is hydrogen, C 1 -C 12 alkyl or phenyl, preferably Y is CH 2 CH 2 -O-CH 2 CH 2 It is.

[0102] According to another embodiment, the composition may include a photoinitiator that is an alkyl-, aryl-, or acyl-substituted compound. In one embodiment, the alkyl-, aryl-, or acyl-substituted photoinitiator has or is centered on an atom of the carbon (group 14) group. In such a case, upon excitation (through absorption of radiation), the group 14 atom present in the photoinitiator compound forms a radical. Thus, such compounds may generate radicals that have or are centered on an atom selected from the group consisting of carbon, silicon, germanium, tin, and lead. In one embodiment, the alkyl-, aryl-, or acyl-substituted photoinitiator is an acylgermanium compound. Such photoinitiators are described in U.S. Pat. No. 9,708,442, assigned to DSM IP Assets BV, the entirety of which is incorporated herein by reference.

[0103] In one embodiment, the composition has the formula: JPEG0007618588000009.jpg42160 (in the above formula, Ar 1 is an aromatic group which is unsubstituted or further substituted at any position by one or more alkyl groups, ethers, sulfides, silyl groups, halogens, carboxyl groups, vinyl groups, additional aromatic or heterocyclic groups, alkyl groups, or aromatic or heterocyclic groups interrupted by one or more ether, sulfide, silyl, carboxyl, or vinyl groups; and R 1 , R 2 , and R 3 comprises photoinitiators that are germanium-based compounds having a structure according to (which may be acyl, aryl, alkyl, or carbonyl groups, independently unsubstituted or further substituted with one or more alkyl groups, ethers, sulfides, silyl groups, halogens, carboxyl groups, vinyl groups, additional aromatic or heterocyclic groups, alkyl groups, or aromatic or heterocyclic groups interrupted by one or more ethers, sulfides, silyls, carboxyl, or vinyl groups). Polymerizable compositions that include acylgermanium compounds are described, inter alia, in U.S. Pat. No. 7,605,190, assigned to Ivoclar Vivadent AG.

[0104] In one embodiment, R 1 -R 3 Each of R is an aryl-substituted or aromatic acyl group. 1 -R 3 Exactly two of the substituents are aryl- or aromatic acyl groups, and the remaining substituents are C 1 -C 10 , or C 1 -C 6 , or C 1 -C 3 In one embodiment, R 1 -R 3 Exactly one of the substituents is an aryl-substituted or aromatic acyl group, and the remaining two substituents are C 1 -C 10 , or C 1 -C 6 , or C 1 -C 3 In another embodiment, R1 -R 3 Each of the C 1 -C 10 , or C 1 -C 6 , or C 1 -C 3 It is an alkyl.

[0105] In one embodiment, the acylgermanium photoinitiator has the following molecular structure: JPEG0007618588000010.jpg48159 is a compound having one of the following structures.

[0106] In one embodiment, the free radical photoinitiator is an acylgermanium compound. In one embodiment, the acylgermanium is benzoyltrimethylgermane (BTG) or bisacylgermanoyl (available as Ivocerin® from Ivoclar Vivadent AG, 9494 Schaan / Liechtenstein).

[0107] Any suitable amount of one or more of the above photoinitiators may be used in the compositions of the present invention and may be selected alone or in combination with one or more of the types listed herein. In a preferred embodiment, the photoinitiator component comprises, consists of, or consists essentially of a free radical photoinitiator. In one embodiment, the photoinitiator component is present in an amount of about 0.1% to about 10% by weight, or about 0.1% to about 5% by weight, or about 1% to about 5% by weight, based on the total weight of the composition.

[0108] [Additives] Additives are also typically added to optical fiber coatings to achieve certain desired properties, such as improved shelf life, improved oxidative and hydrolytic stability of the coating, etc. There are many different types of desirable additives, and the invention discussed herein is not intended to be limited by these, but they are included in the contemplated embodiments because they have desirable effects.

[0109] Examples of these are thermal inhibitors intended to prevent premature polymerization, examples being hydroquinone, hydroquinone derivatives, p-methoxyphenol, beta-naphthol or sterically hindered phenols such as 2,6-di(tert-butyl)-p-cresol. The shelf life in the dark can be extended by using copper compounds such as copper naphthenate, copper stearate or copper octoate, phosphorus compounds such as triphenylphosphine, tributylphosphine, triethyl phosphite, triphenyl phosphite or tribenzyl phosphite, quaternary ammonium compounds such as tetramethylammonium chloride or trimethylbenzylammonium chloride.

[0110] Paraffin or similar wax-like substances can be added to keep out atmospheric oxygen during polymerization; due to their low solubility in the polymer, they migrate to the surface at the start of polymerization and form a transparent surface layer that prevents air from entering. Similarly, an oxygen barrier layer can be applied.

[0111] Light stabilizers which can be added are UV absorbers, for example well-known commercially available UV absorbers of the hydroxyphenylbenzotriazole, hydroxyphenyl-benzophenone, oxalamide or hydroxyphenyl-s-triazine type. It is possible to use such compounds individually or mixtures thereof, with or without the use of sterically hindered relatively non-basic amine light stabilizers (HALS). Sterically hindered amines are, for example, based on 2,2,6,6-tetramethylpiperidine. UV absorbers and sterically hindered amines are, for example:

[0112] 2-(2-Hydroxyphenyl)-2H-benzotriazole, e.g., U.S. Pat. Nos. 3004896; 3055896; 3072585; No. 4127586; No. 4226763; No. 4275004; No. 4278589; No. 4315848; No. 4347180; No. 4383863; No. 4675352; No. 4681905, No. 4853471; No. 5268450 Nos. 5,278,314, 5,280,124, 5,319,091, 5,410,071, 5,436,349, 5,516,914, 5,554,760, 5,563,242, 5,574,166, 5,607,987, 5,977,219 and 6,166,218, the known commercially available hydroxyphenyl-2H-benzotriazoles and benzotriazoles, such as 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole, 2-(3,5-diphenylphenyl)-2H-benzotriazole, -t-butyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)-2H-benzotriazole, 5-chloro-2-(3,5-di-t-butyl-2-hydroxyphenyl)-2H-benzotriazole, 5-chloro-2-(3-t-butyl-2-hydroxy-5-methylphenyl)-2H-benzotriazole, 2-(3-sec-butyl 2-(2-hydroxy-4-octyloxyphenyl)-2H-benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(3,5-bis-α-cumyl-2-hydroxyphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-(ω-hydroxy-octa-(ethyleneoxy)carbonyl-ethyl)-,phenyl)-2H-benzotriazole, 2-(3-dodecyl-2-hydroxy-5-methylphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-octyloxycarbonyl)ethylphenyl)-2H-benzotriazole, dodecylated 2-(2-hydroxy-5-methylphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-octyloxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole, 2-(3-tert-butyl-5-(2-(2-ethylhexyloxy)-carbonylethyl)-2-hydroxyphenyl)-5-chloro-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-methoxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-methoxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole, 2-(3-t-butyl-5-(2-(2-ethylhexyloxy)carbonylethyl)-2-hydroxyphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-isooctyloxycarbonylethyl)phenyl-2H-benzotriazole, 2,2'-methylene-bis(4-t-octyloxycarbonylethyl)phenyl 2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole, 2-(2-hydroxy-3-t-octyl-5-α-cumylphenyl)-2H-benzotriazole, 5-fluoro-2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole, 5-chloro-2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole, 5-chloro-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-(2-isooctyloxycarbonylethyl)phenyl)-5-chloro-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-5-t-octylphenyl)-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-3,5-di-t-octylphenyl)-2H-benzotriazole, methyl 3-(5-trifluoromethyl-2H-benzotriazol-2-yl)-5- t-Butyl-4-hydroxyhydrocinnamate, 5-butylsulfonyl-2-(2-hydroxy-3-α-cumyl-5-t-octylphenyl)-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-3-α-cumyl-5-t-butylphenyl)-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole, 5-trifluoromethyl-2-(2-hydroxy-3,5-di-α-cumylphenyl)-2H-benzotriazole, 5-butylsulfonyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole and 5-phenylsulfonyl-2-(2-hydroxy-3,5-di-t-butylphenyl)-2H-benzotriazole.

[0113] 2-Hydroxybenzophenones, such as the 4-hydroxy, 4-methoxy, 4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2',4'-trihydroxy and 2'-hydroxy-4,4'-dimethoxy derivatives.

[0114] Esters of substituted and unsubstituted benzoic acids, for example, 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis(4-tert-butylbenzoyl)resorcinol, benzoylresorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate.

[0115] To accelerate the photopolymerization, it is possible to add accelerators, such as thiols, thioethers, disulfides and phosphines, coinitiators and autoxidizers, as described, for example, in EP-A-438123 and GB-A-2180358.

[0116] Photopolymerization can also be accelerated by adding photosensitizers that shift or broaden the spectral sensitivity. These are especially aromatic carbonyl compounds, such as benzophenone derivatives, thioxanthone derivatives, anthraquinone derivatives and 3-acylcumarine derivatives, as well as 3-(aroylmethylene)thiazolines, and eosin, rhodamine and erythrosine dyes. Alternatively, non-aromatic carbonyl compounds may be used. An example of a non-aromatic carbonyl is dimethoxyanthracene.

[0117] The curing procedure may be assisted in particular by pigmented compositions (for example with titanium dioxide) and also by adding components which form free radicals under thermal conditions, for example azo compounds such as 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), triazenes, diazosulfides, pentaazadienes, or peroxy compounds such as hydroperoxides or peroxycarbonates, for example t-butyl hydroperoxide, as described in US Patent No. 4,753,817. Further suitable for this purpose are benzopinacol compounds.

[0118] The novel compositions may also contain photoreducible dyes, such as xanthene, benzoxanthene, benzothioxanthene, thiazine, pyronine, porphyrin or acridine dyes, and / or trihalomethyl compounds that can be cleaved by radiation.Similar compositions are described, for example, in US Pat. No. 5,229,253.

[0119] Other conventional additives may be used depending on the intended use. Examples include optical brighteners, fillers, pigments, dyes, wetting agents or leveling aids. For thick pigmented coatings, glass microbeads or powdered glass fibers may also be included, as described, for example, in U.S. Pat. No. 5,013,768.

[0120] In a preferred embodiment, the additive component includes one or more adhesion promoting compounds. Such adhesion promoters provide a bond between the polymer primary coating and the surface of the optical glass fiber. Silane coupling agents that are hydrolyzable have been used as glass adhesion promoters. Silane coupling agents have the general structure (RO): 3The adhesive agent has the formula -Si-R'-X, where X is an organic functional group, R' is an alkylene bond, and RO is a hydrolyzable group (such as an alkoxy group). Such agents are described, inter alia, in U.S. Pat. No. 4,932,750. In one embodiment, the adhesion promoter is a hydrolyzable silane compound containing a mercapto group and / or multiple alkoxy groups. Such adhesion promoters are known and are described in U.S. Patent Application No. 20020013383, the relevant portions of which are incorporated herein by reference.

[0121] In one embodiment, the adhesion promoter comprises one or more of gamma-mercaptopropyltrimethoxysilane, trimethoxysilylpropyl acrylate, or 3-trimethoxysilylpropane-1-thiol. Alternatively, the silane coupling groups can be reacted onto the oligomer in the oligomeric component; in such cases, they are considered part of the oligomeric component, rather than as an additive. Whether used as an additive or in an oligomer, it is highly preferred to utilize an adhesion promoter compound to ensure that the coating adheres (and remains adhered) adequately to the outer surface of the corresponding glass optical fiber during processing and use.

[0122] Any suitable amount of one or more of the additives described above may be used in the compositions of the present invention, and may be selected alone or in combination with one or more of the types listed herein. In a preferred embodiment, the additive component is present in an amount of about 0.01% to about 5% by weight, more preferably about 0.1% to about 2% by weight, based on the total weight of the composition. According to another embodiment, one or more of the additives described above are included in an amount of about 1% to about 5% by weight.

[0123] A second aspect of the invention is a method for coating an optical fiber comprising providing a glass optical fiber; applying a primary coating composition to a surface of the glass optical fiber; optionally providing UV light in an amount sufficient to at least partially cure said primary coating composition; applying a secondary coating composition to the primary coating composition; exposing the primary coating composition and the secondary coating composition to at least one radiation source capable of emitting ultraviolet radiation to affect curing of said primary coating composition and said secondary coating composition to form a cured primary coating on the surface of the optical fiber and a cured secondary coating on the surface of the cured primary coating; wherein the primary coating composition is a composition according to any of the embodiments of the first aspect of the invention.

[0124] Preferably, the glass optical fiber is provided by drawing said optical fiber through a draw tower in a manner well understood by those skilled in the art of producing optical fiber coatings.

[0125] Another embodiment of the fourth aspect describes a method of coating optical fiber according to one of the following conditions: a drawing speed greater than 1500 m / min, or greater than 1700 m / min, or greater than 2000 m / min, or greater than 2500 m / min, or greater than 3000 m / min and less than 5000 m / min, or less than 4000 m / min, or less than 3100 m / min; or without the application of helium, or with the application of helium at a flow rate of less than 20 standard liters per minute (SLM), less than 10 SLM, less than 5 SLM, or 1 to 20 SLM, or 1 to 10 SLM, or 1 to 5 SLM, or 5 to 20 SLM, or 5 to 10 SLM.

[0126] A third aspect of the invention is a coated optical fiber comprising a glass core, a cladding layer in contact with and surrounding the glass core, and a coating further comprising a primary coating layer in contact with and surrounding the cladding layer, and a secondary coating layer in contact with and surrounding the primary coating layer. According to this third aspect, the primary coating layer is a cured product of a radiation curable composition according to any of the embodiments of the first aspect.

[0127] Coated optical fibers according to embodiments of the third aspect are shown in Figures 3 and 4. Figure 3 shows a side view of a fiber 10 as considered herein, while Figure 4 shows a cross-sectional view of a fiber 10 as an example of the result of the coated fibers described herein.

[0128] Optical fiber 10 includes a core 11, a cladding 12, a primary coating 13 that contacts and surrounds an outer annular cladding region, and a secondary coating 14. The outer diameter of core 11 is D 1 and the outer diameter of the cladding 12 is D 2The primary coating 13 is a typical primary coating having an in situ (or on fiber) tensile modulus of less than 1.5 MPa, or less than 1.2 MPa, or as low as 0.35 MPa, 0.3 MPa, or 0.25 MPa, and in other embodiments, 0.2 MPa or less. Methods for describing the in situ modulus are well known in the art and are described, inter alia, in U.S. Pat. No. 7,171,103 and U.S. Pat. No. 6,961,508, each of which is assigned to DSM IP Astests BV. The cured primary coating 13 has an in situ glass transition temperature of less than -35°C, or less than -40°C, or less than -45°C, and in other embodiments, less than -50°C. A primary coating with a low in situ modulus reduces microbending, which is a coupling mechanism between modes propagating in the fiber. A low in situ glass transition temperature ensures that the in situ modulus of the primary coating remains low even when the fiber is laid in a very cold environment. Thus, the microbending performance is stable over temperature, and low mode coupling is obtained in all circumstances. The secondary coating 14 contacts and surrounds the primary coating 13. The secondary coating 14 has an in situ tensile modulus greater than 800 MPa, or greater than 1110 MPa, or greater than 1300 MPa, or greater than 1400 MPa, or greater than 1500 MPa. A secondary coating with a high in situ modulus reduces microbending, which is a coupling mechanism between modes propagating in the fiber.

[0129] In the embodiment shown and described herein, the core 11 is made of pure silica glass (SiO 2 ) or silica glass containing one or more dopants that increase the refractive index of the glass core relative to pure undoped silica glass. Suitable dopants for increasing the refractive index of the core include, but are not limited to, GeO 2 , Al 2 O 3 , P 2 O 5 , TiO 2 , ZrO 2 , Nb 2 O 5, Ta 2 O 5 , and / or combinations thereof. The cladding 12 is made of pure silica glass (SiO 2 ), or one or more dopants that increase the refractive index, such as when the cladding is "updoped" (GeO 2 , Al 2 O 3 , P 2 O 5 , TiO 2 , ZrO 2 , Nb 2 O 5 , and / or Ta 2 O 5 ) or when the inner cladding is “down-doped”, the maximum relative refractive index of the core 11 [Δ 1MAX ] is the maximum relative refractive index of the cladding 12 [Δ 4MAX

[0033] may comprise silica glass containing a refractive index lowering dopant such as fluorine. According to one embodiment, the cladding 12 is pure silica glass.

[0130] In the embodiment of the third aspect of the invention, any optical fiber type can be used, however in a preferred embodiment the coated optical fiber has a mode field diameter of 8 to 10 μm at a wavelength of 1310 nm, or a mode field diameter of 9 to 13 μm at a wavelength of 1550 nm, and / or a mode field diameter of 20 to 200 μm. 2 Such fibers may be single mode and / or large effective area fibers, given the expected demand for coating processes for these fibers to utilize faster line or processing speeds, however, other fiber types such as multimode fibers may also be used.

[0131] The primary coating 13 preferably has a higher refractive index than the cladding 12 of the optical fiber 10 to enable removal of optical signals that have strayed from the core of the optical fiber. For example, an exemplary transmission optical fiber 10 may have refractive index values ​​at a wavelength of 1550 nm of 1.447 and 1.436 for the core and cladding, respectively; therefore, it is desirable for the refractive index of the primary coating 13 to be greater than 1.44 at 1550 nm. The primary coating 13 maintains sufficient adhesion to the glass fiber during thermal and hydrolytic aging, but can be stripped from the glass fiber for splicing purposes (if necessary). The primary coating 13 typically has a thickness in the range of 20-50 μm (e.g., about 25 or 32.5 μm), with a thinner thickness in the range of 15-25 μm for 200 μm fibers.

[0132] Coating 13 is a primary coating and is typically applied directly to the glass fiber. Coating 13 preferably has a low in situ modulus and a low in situ T g The flexible crosslinked polymer material has a

[0133] The primary coating 13 preferably has a thickness of less than about 40 μm, more preferably between about 20 and about 40 μm, and most preferably between about 20 and about 30 μm. As described in more detail herein below, the primary coating 13 is typically applied to the glass fiber and then cured. Various additives may also be present that enhance one or more properties of the primary coating, including antioxidants, adhesion promoters, PAG compounds, photosensitizers, carrier surfactants, tackifiers, catalysts, stabilizers, surface agents, and optical brighteners of the types described above.

[0134] As mentioned above, the primary coating composition may be selected from any of the embodiments of the first aspect of the invention described elsewhere herein. In one embodiment, a suitable primary coating composition may include, but is not limited to, about 10 to 95 weight percent, or 10 to 90 weight percent, or about 25 to about 75 weight percent of one or more urethane acrylate oligomers; about 10 to about 65 weight percent, more preferably about 25 to about 65 weight percent of one or more monofunctional ethylenically unsaturated monomers; about 0 to about 10 weight percent of one or more multifunctional ethylenically unsaturated monomers; about 1 to about 5 weight percent of one or more photoinitiators; about 0.5 to about 1.5 pph of one or more antioxidants; optionally about 0.5 to about 1.5 pph of one or more adhesion promoters; optionally about 0.1 to about 10 pph of a PAG compound; and about 0.01 to about 0.5 pph of one or more stabilizers.

[0135] Coating 14 is an outer coating and serves the traditional purpose of a "secondary coating." Outer coating material 14 is, for example, the polymerization product of a coating composition whose molecules are highly crosslinked upon polymerization. In the embodiments described herein, coating 14 has a high in situ modulus (e.g., greater than about 800 MPa at 25° C.) and a high T g (e.g., greater than about 50° C.). The in situ secondary modulus is preferably greater than about 1000 MPa, more preferably greater than about 1100 MPa, and most preferably greater than about 1200 MPa. According to some preferred embodiments, the in situ secondary modulus is greater than 1200 MPa. In other preferred embodiments, the in situ secondary modulus is between about 1000 MPa and about 8000 MPa, more preferably between about 1200 MPa and about 5000 MPa, and most preferably between about 1500 MPa and about 3000 MPa. The in situ T of the secondary coating g is preferably between about 50° C. and about 120° C., more preferably between about 50° C. and about 100° C. In one embodiment, the secondary coating 14 has a thickness of less than about 40 μm, more preferably between about 20 and about 40 μm, and most preferably between about 20 and about 30 μm.

[0136] Other suitable materials for use in outer (or secondary) coating materials, as well as the considerations associated with the selection of these materials, are well known in the art and are described, for example, in U.S. Patents 4,962,992 and 5,104,433 to Chapin. As an alternative to these, high modulus coatings have also been obtained using coating systems with low oligomer content, as described in U.S. Patents 6,775,451 to Botelho et al. and 6,689,463 to Chou et al. In addition, non-reactive oligomeric components have been used to achieve high modulus coatings, as described in U.S. Patent Application Publication No. 20070100039 to Schissel et al. As described in more detail herein below, the outer coating is typically applied (with or without prior curing) to a previously coated fiber and then cured. Various additives may also be present that improve one or more properties of the coating, including antioxidants, PAG compounds, photosensitizers, catalysts, lubricants, low molecular weight non-crosslinked resins, stabilizers, surfactants, surface agents, slip additives, waxes, micronized polytetrafluoroethylene, and the like. The secondary coating may also include inks, as is well known in the art.

[0137] Suitable compositions for the secondary or outer coating 14 include, but are not limited to, about 0 to 70 weight percent of one or more urethane acrylate oligomers; about 20 to about 95 weight percent of one or more multifunctional ethylenically unsaturated monomers; about 0 to about 10 weight percent of one or more monofunctional ethylenically unsaturated monomers; about 1 to about 5 weight percent of one or more photoinitiators; about 0 to about 5 pph of one or more slip additives; and about 0.5 to about 1.5 pph of one or more antioxidants.

[0138] It is known in the art how to formulate typical optical fiber coatings for such fiber primary and secondary coatings, as well as inks and matrix materials for curing using broadband UV lamps. A good discussion of the chemistry and test methods associated with this technology can be found in the textbook "Specialty Optical Fibers Handbook" by A. Mendez and TF Forse, published by Elsevier, copyright Elsevier Inc. 2007, from Chapter 4, Section 4.6 to the end.

[0139] A fourth aspect of the present invention is an optical fiber cable, wherein the optical fiber comprises at least one optical fiber according to the third aspect of the invention, and / or the optical fiber is a cured product of a composition according to the first aspect of the invention, and / or the optical fiber is coated according to the second aspect of the invention.

[0140] The improved compositions of the present invention may be formulated through the selection of the ingredients identified herein above, and may further be readily tailored by those skilled in the art to which this invention applies by following the formulation guidelines herein, as well as by extrapolating from the general approaches taken in the embodiments illustrated in the following examples, which further illustrate the present invention but, of course, should not be construed as in any way limiting its scope. EXAMPLES

[0141] These examples illustrate embodiments of the present invention. Table 1 lists the various components of the compositions used in the examples. Table 2A lists the relative amounts of the reagents listed in Table 1 that were used to synthesize the oligomers used in the examples. Table 2B presents further evaluation of selected reactive diluent monomers and reactive oligomers, respectively. JPEG0007618588000011.jpg253170JPEG0007618588000012.jpg36170JPEG0007618588000013.jpg246165

[0142] [Synthesis of Oligomers 1-18] First, the specified amount of the appropriate polyol from Table 2A (e.g., 84.06 parts of PPG2000 for Oligomer 1) was charged to a 250 ml reactor (equipped with agitator, air inlet, dropping funnel, and condenser). After charging, the reactor was heated to 45° C., and then the reactor was purged with dry lean air. Next, the specified amount of the appropriate isocyanate (e.g., 10.97 parts of TDI for Oligomer 1) was charged to the reactor with stirring. After this step, the corresponding amount of DBTDL (e.g., 0.05 parts for Oligomer 1) was added to the reactor. After waiting 1 hour for the reaction to start, the temperature was then increased to 60° C. The temperature of 60° C. was then maintained for an additional 2 hours. After this additional 2 hours of reaction time, the isocyanate (NCO) content was measured by potentiometric titration and found to be within 10% of the theoretical isocyanate content value that can be derived for the oligomer from the amounts specified in Table 2A above. If the measured value was not within 10%, the reaction was continued for additional 15 minute increments until such a value was achieved and then rechecked. Once the appropriate isocyanate content was confirmed, the specified amount of the appropriate end-capping surface agent (e.g., 4.88 parts HEA for Oligomer 1) was added to the mixture along with the specified amount of BHT (e.g., 0.05 parts for Oligomer 1). The temperature was then increased to 85°C. The resulting mixture was allowed to react for an additional hour at 85°C. After accounting for this additional hour of reaction time, the NCO content was checked again by potentiometric titration. The reaction was considered complete when the isocyanate content was less than 0.1% based on the total weight of the composition. If the isocyanate content was not below this value, the mixture was returned to the reaction chamber (again at 85°C) for additional 15 minute increments and checked again, and this step was repeated until the isocyanate content was within the desired range. Finally, the resulting synthetic oligomer was slowly cooled and discharged for use in the experiments described elsewhere herein.

[0143] [Synthesis of Oligomer 11O (outside-in)] First, the specified amount of hydroxyethyl methacrylate for Oligomer 11 from Table 2A (e.g., 1.57 parts of HEMA) was charged into a 250 ml reactor (equipped with a stirrer, air inlet, dropping funnel, and condenser) along with the specified amount of BHT (e.g., 0.05 parts for Oligomer 11). After charging, the reactor was heated to 45° C., and then the reactor was purged with dry lean air. Next, the specified amount of the corresponding isocyanate (e.g., 3.15 parts of TDI for Oligomer 11) was charged into the reactor with stirring. After this step, the corresponding amount of DBTDL (e.g., 0.05 parts for Oligomer 1) was added to the reactor. After waiting 1 hour for the reaction to start, the temperature was then increased to 60° C. The temperature of 60° C. was then maintained for an additional 2 hours. After this 2 hour additional reaction time, the isocyanate (NCO) content was measured by potentiometric titration and confirmed to be within 10% of the theoretical isocyanate content value that could be derived for the oligomer from the amount specified in Table 2A above. If the measured value was not within 10%, the reaction was continued for additional 15 minute increments until such a value was achieved and then rechecked. Once the appropriate isocyanate content was confirmed, the specified amount of the appropriate polyol (e.g., 95.18 parts PPG 8000 for Oligomer 11) was added to the mixture. The temperature was then increased to 85°C. The resulting mixture was allowed to react for an additional hour at 85°C. After accounting for this additional hour of reaction time, the NCO content was checked again by potentiometric titration. The reaction was considered complete when the isocyanate content was less than 0.1% based on the total weight of the composition. If the isocyanate content was not below this value, the mixture was returned to the reaction chamber (again at 85°C) for additional increments of 15 minutes and checked again, and this step was repeated until the isocyanate content was within the desired range. Finally, the resulting synthetic oligomer was slowly cooled and discharged for use in the experiments described elsewhere herein.

[0144] [Synthesis of Oligomers 19-21] First, a reaction vessel equipped with an agitator, air inlet, dropping funnel, and condenser was charged with the specified amount of the appropriate polyol from Table 2A (e.g., 89.218 parts of PPG 3000 for Oligomer 19). Next, with stirring, the specified amount of the appropriate isocyanate (e.g., 7.395 parts of TDI for Oligomer 19) was added, followed by the associated amount of BHT (0.024 parts for each of Oligomers 19-21). After heating to 40°C, a specified amount of DBTDL (0.027 parts for each of Oligomers 19-21) was added. After waiting 1 hour for the reaction to start, the temperature was slowly increased to 60°C. The temperature of 60°C was then maintained for an additional 2 hours. After this 2 hour reaction time, the isocyanate (NCO) content was measured by potentiometric titration and found to be within 10% of the theoretical isocyanate content value that can be derived for the oligomer from the amounts specified in Table 2A above. If the measured value was not within 10%, the reaction was continued and rechecked in additional 15 minute increments until such a value was achieved. Once the appropriate isocyanate content was confirmed, the temperature was raised to 70°C and the appropriate amount of the first end cap (e.g., HEA for Oligomer 19) was added. The resulting mixture was allowed to react at about 70°C for 2 hours. After the residual isocyanate group concentration was reduced to within 10% of the theoretical content per measurement every 15 minutes using a potentiometric titrator, a specified amount of 2-ethylhexanol (e.g., 0.921 parts EH for Oligomer 19) was added and the reaction was allowed to continue for another 2 hours. After accounting for this additional hour of reaction time, the NCO content was checked again by potentiometric titration. The reaction was considered to be complete when the isocyanate content was less than 0.1% based on the total weight of the composition. If the isocyanate content was not below this value, the mixture was returned to the reaction chamber in additional 15 minute increments and checked again, and this step was repeated until the isocyanate content was within the desired range. Finally, the resulting synthetic oligomer was slowly cooled and discharged for use in the experiments described elsewhere herein.

[0145] [Synthesis of Oligomers 22-26] A 500 ml reactor equipped with an agitator, air inlet, dropping funnel, and condenser was first purged with dry air, and then the amounts of glycerol monomethacrylate and food grade butylated hydroxytoluene specified in Table 2A above (e.g., 0.94 and 0.03 parts for oligomers 22 and 23, respectively) were charged to the reactor at room temperature. Next, the specified amount of diisocyanate (TDI) was charged to the reactor with continued agitation. After the initial exotherm, 0.006 parts of DBTDL were added to the reactor. After 30 minutes, the temperature was increased to 45° C., at which point the specified amount of the specified polyol was charged to the reactor. After the addition of the polyol, an additional 0.02 parts of DBTDL was added to the reactor and the temperature was increased to 60° C. The temperature of 60° C. was then maintained for an additional 2 hours. After this two hour period, the isocyanate (NCO) content was measured by potentiometric titration to ensure that it was within 10% of the theoretical isocyanate content value that could be derived for each oligomer from the amounts specified in Table 2A above. If the measured value was not within 10%, the reaction was continued and rechecked for additional 15 minute increments until such a value was achieved. Once the appropriate isocyanate content was confirmed, a specified amount of the designated end cap (e.g., 1.53 parts HEMA for Oligomer 22) was added, after which the temperature was increased to 85°C and the resulting mixture was allowed to react for an additional hour at 85°C. After this hour of reaction, the NCO content was checked again by potentiometric titration. The reaction was considered complete when the isocyanate content was less than 0.1% based on the total weight of the composition. If the isocyanate content was not below this value, the mixture was returned to the reaction chamber for additional 15 minute increments and checked again, and this step was repeated until the isocyanate content was within the desired range. Finally, the resulting synthetic oligomer was slowly cooled and discharged for use in the experiments described elsewhere herein.

[0146] [Characterization of reactive oligomers] After synthesis of various reactive oligomers, they were evaluated according to the size-exclusion chromatography (SEC) method according to ASTM: D5296-11: “Standard Test Method for Molecular Weight Averages and Molecular Weight Distribution of Polystyrene by High Performance Size-Exclusion Chromatography,” ASTM International, West Conshohocken, PA, (2011). In addition, ASTM standard D 5226-98: “Standard Practice for Dissolving Polymer Materials,” ASTM International, West Conshohocken, PA, (2010) was used to facilitate the definition of suitable solvents for polymer analysis.

[0147] Specifically, all size exclusion chromatography measurements were performed on a Viscotek GPCMax VE2001 solvent / sample module system further equipped with a TDA302 triple detector array. Three PFG Linear XL columns from PSS Polymer Standards Service GmbH were used for chromatographic separation. The detectors and columns were operated at 35°C. Prior to SEC, with one exception, each respective polymer was dissolved in hexafluoroisopropanol (HFIP) containing 0.1 wt% potassium trifluoroacetate at concentrations ranging from 1.0 to 1.5 mg / ml, which was also used as the eluent in the SEC analysis at a flow rate of 0.8 ml / min. The only exception to this was oligomer 12, which was dissolved in tetrahydrofuran since it was not readily soluble in HFIP.

[0148] After dissolution was complete, the molar mass and molar mass distribution were then determined by the triple detection method described above using refractive index, differential viscosity, and right-angle light scattering signals. A fixed refractive index increment (dn / dc) of 0.215 ml / g was used to calculate the molecular weight average and molar mass distribution. The refractive index increment and molecular weight average, as well as the molar mass distribution, were determined by integration of the entire refractive index chromatogram. The IV-DP signal was additionally used to set the integration limits. The recovery of the samples from the column varied between 95% and 105%, which are typical values ​​obtained with size exclusion chromatography.

[0149] Using this method, number average (Mn), weight average (Mw), peak (Mp), and Z average (Mz) molecular weight values ​​were recorded and are reported in Table 2B along with the theoretical molecular weight (Mn,theo), which was calculated using the molecular weights of the individual reactants (listed in Table 1) in the ratios listed in the "Molar Ratio" column (where P=polyol; ISO=diisocyanate; A / MA=acrylate and / or methacrylate; OH=hydroxyl group-containing components with no polymerizable groups). JPEG0007618588000014.jpg229170

[0150] [Determination of reactivity ratio] To determine the reactivity ratios, RT-FTIR was used to monitor the conversion of the different components according to JFGA Jansen, Erwin EJE Houben, Peter HG Tummers, Dietrich Wienke, John Hoffmann, “Real-Time Infrared Determination of Photoinitiated Copolymerization Reactivity Ratios: Application of the Hilbert Transform and Critical Evaluation of Data Analysis Techniques”. Macromolecules, 37, 2275 (2004). Multivariate analysis was performed using the IR spectra of the pure components as input.

[0151] Specifically, the reactivity ratios of several methacrylate monomers used in the oligomers described herein above were determined in copolymerization with 2-hydroxyethyl acrylate (HEA). 1 represents the self-reactivity ratio of a component with itself, and R 2 represents its relative reactivity ratio with the associated HEA. The results are reported in Table 2C below. JPEG0007618588000015.jpg38169

[0152] [Formulation 1-99] Each of the formulations set forth in Tables 3A-3E below was prepared using a Speedmixer TM The mixture was prepared in a standard manner by using a 50 ml mixing cup suitable for use with the Speedmixer. Specifically, 1 part by weight of photoinitiator TPO was added to the amount of oligomer specified in Tables 3A to 3E below, followed by the specified amount of monomer to make a total of 10 g. The cup was then closed and the mixture was mixed in a Speedmixer. TM The DAC150FVZ was mixed vigorously for 30 seconds, stopped, and mixed again in the same manner for an additional 30 seconds.

[0153] These samples were analyzed to determine the mole percent of methacrylate groups in each formulation, T 30%,modulusmax The properties were tested according to the methods described below to determine MaxG', MaxG', and MaxG', respectively. The values ​​for mole percent of methacrylate groups are rounded to one decimal place while the other values ​​are rounded to two decimal places. The values ​​of these measured properties are reported in Tables 3A-3E below.

[0154] [Calculation of the mole fraction of various polymerizable groups] The mole fractions of the various polymerizable groups were determined by a calculation-based method using theoretical molecular weight values ​​(Mn,theo) as described further herein, although measurement-based methods will also be understood by those skilled in the art to which the present invention applies for situations where Mn,theo values ​​are not available. As reported herein, the mole fractions are determined by dividing the molar amount of the desired polymerizable group type by the molar amount of all polymerizable groups in a particular compositional component (or the entire composition itself, as specified). The molar amounts are determined by summing the molar amounts of each relevant polymerizable group-containing compositional component, with the value for each component being calculated according to the following formula: The Mn,theo values ​​for the oligomers and monomers used herein are reported in Table 2B above.

[0155] For purposes herein, all methacrylate, acrylate, acrylamide, and N-vinylamide groups are considered to be polymerizable groups, although other such groups for other formulations not shown herein will be readily apparent to those skilled in the art to which this invention applies. For the avoidance of doubt, hydroxyl groups are not considered to be polymerizable groups herein. Using the molar amount calculation methodology described above, two different types of mole fraction values ​​for each formulation were determined (reported in Tables 3A through 3E below): "% MA Oligomer" and "% AAN Monomer."

[0156] In the column headed "%MA Oligomer," the values ​​presented in Tables 3A-3E below represent the mole fraction of methacrylate groups in the oligomer component relative to all polymerizable groups in the oligomer component. As an example, Formulation 45 (whose oligomer component consists of equal parts by weight of reactive oligomers PPG8diHEMA and PPG8diHEA) has a "%MA Oligomer" value of 49.96%. Because the theoretical molecular weight of PPG8diHEMA is slightly higher than its acrylate analog, such value was determined to be less than 50%. An illustrative calculation for this is shown in Table 2D below. JPEG0007618588000017.jpg50170

[0157] The "% MA Oligomer" value was then determined by calculating 0.004129 / 0.008265 and then expressing that value as a % (ie, x 100).

[0158] Alternatively, under the column headed "% AAN Monomer," the mole fraction of acrylate, acrylamide, and N-vinylamide groups in the total reactive diluent monomer component was determined as a fraction out of all polymerizable groups in the reactive diluent monomer component. As an example, the "% AAN Monomer" for Formulation 15 was 93.7%, and the calculation is shown below in Table 2E. JPEG0007618588000018.jpg44170

[0159] The "% AAN Monomer" value was then determined by calculating 0.1509 / 0.1611 and then expressing that value as a % (i.e., x 100).

[0160] Finally, in the column headed "Mol%Meth", the mole fraction of all methacrylate groups in the total composition was determined as a percentage of all polymerizable groups in the total composition. As an example, the "Mol%Meth" for Formulation 98 was 6.6%, the basis for which is shown in Table 2F below. JPEG0007618588000019.jpg42170

[0161] The "% Mol Meth" value was then determined by calculating 0.0120 / 0.1812 and expressing that value as a % (ie, x 100).

[0162] [Maximum elastic modulus (G') and T 30%,modulus max Value Determination Maximum elastic modulus (G') values ​​were determined according to the following procedure described herein. The hardware / equipment used in this procedure was as follows: [Rheometer + accessories] ARESG2-Rheometer (Manufacturer: TA Instruments) APS temperature control device (Advanced Peltier System) APS standard flat plate (lower geometry) ARESG2 UV curing accessories (top plate fixture, UV light shield bag and access door, collimating optics) Φ20mm acrylic plate (upper geometry) with UV curing option top plate fixture SilverlineUV radiometer, UV light sensor (not calibrated), UV sensor geometry and disposable plate holder [UV light source, etc.] Omnicure LX500 with included 385nm LED and 8mm lens Moeller Easy 412-DC-TC Control Relay (Trigger Box) UV Power Pack II (Electronic Instrumentation & Technology, calibrated)

[0163] Next, the above hardware was set up and arranged as follows: First, UV curing measurements were performed on an ARESG2 rheometer (TA Instruments). The rheometer was equipped with an APS temperature controller, an APS standard flat plate as the lower geometry, and an ARESG2 UV curing option. The upper geometry used was the upper plate fixture of the ARESG2 UV curing option combined with a 20 mm diameter acrylic plate. As the UV light source, an Omnicure LX500 spot curing system was used in combination with a 385 nm LED (8 mm lens). Then, the 385 nm LED was inserted into the collimating optical lens of the ARESG2 UV curing accessory. The collimating lens was fixed to the light shield and aligned to the upper UV geometry mirror, and the alignment screws were tightened. The diameter of the original 5 mm light guide holder part of the collimating lens was expanded to 12 mm to accommodate the 385 nm UV-LED.

[0164] An Omnicure LX500 spot curing system was then connected to the DIGITAL I / O connector of the ARESG2 via a Moeller Easy 412-DC-TC control relay. The control relay acted as a trigger box for the UV light source. The trigger delay time was set to 1.5 seconds, which means that the 385 nm UV-LED was automatically switched on with a delay of 1.5 seconds after the start of data collection for the elastic modulus measurement on the ARESG2. The light intensity was set to 95% and the UV light duration was fixed at 128 seconds.

[0165] UV Light Alignment: Alignment was performed before installing the APS temperature control unit. The UV sensor geometry was mounted on the disposable plate holder and set as the lower geometry. The UV light sensor connected to the Silverline UV radiometer was placed in the outer hole of the UV sensor geometry. The upper geometry was placed on top of the UV light sensor by applying an axial force of about 100 grams. The light intensity was then measured at four positions by rotating the lower geometry by about 90° between each successive measurement. The alignment of the collimating lens was then adjusted with the alignment screws of the light shield to achieve the most even light distribution possible at each point. The difference in light intensity at the four different positions was kept below 10%.

[0166] Determination of light intensity: Prior to the RT-DMA measurements, the UV intensity was measured with the help of a calibrated UV Power Pack II. To achieve this, the sensor of the UV Power Pack II was placed directly under (distance <0.5 mm) the surface of the 20 mm acrylic plate of the upper plate fixture, so that the surface of the acrylic plate completely covered the sensor surface. Then, the Omnicure LX500 UV light source (intensity value set to 95%) was manually switched on for 10 seconds. During this 10 seconds, the UVA2 intensity (i.e., radiation between the wavelengths of 380-410 nm) was measured by the UV Power Pack II instrument. The measured UVA2 intensity was 60-70 mW / cm 2 was determined to be 67 mW / cm 2 The actual values ​​were recorded.

[0167] Determining the actual delay time: When starting the measurement, there was a delay between the start of data sampling and the start of UV exposure. In the settings of the Moeller Easy 412-DC-TC control relay, the delay was set to 1.5 seconds, which meant that UV exposure started 1.5 seconds after the start of data sampling.

[0168] With the aid of a light dependent resistor (LDR) and an oscilloscope (PicoScope 3424), the actual delay time of 1.519 seconds was measured, which was the measured average value of 10 individual measurements with a standard deviation of 0.004 seconds.

[0169] RT-DMA Measurements: RT-DMA UV cure measurements were then performed using an ARESG2 rheometer paired with an Advanced Peltier System as the temperature controller, an APS flat plate, and an ARESG2 UV cure accessory setup. A 385 nm LED with an 8 mm lens connected to an Omnicure LX500 was used as the UV light source.

[0170] Sample Loading: Before loading each respective sample, the temperature of the lower plate was set to 50°C. When the temperature reached 50°C, the surface of the upper plate (which was a 20mm thick acrylic plate) was brought into contact with the lower plate by applying an axial force of 200-400 grams, i.e., a gap of 0mm, thereby allowing the upper parallel plate to equilibrate to the set temperature of 50°C. The system was allowed to further equilibrate its temperature for at least 5 minutes after the initial contact. Next, a zero fixture procedure was performed according to well-known methods to determine the position of Gap=0. After determining the position of Gap=0, the upper plate was moved to a position 10mm away. A portion of each respective sample was then moved to the center of the lower plate with the tip of a small spatula, after which the upper geometry was lowered to a position of Gap=0.120mm. The amount of sample had to be sufficient to ensure that the excess was pushed outside the gap covering the entire circumference of the upper parallel plate after the upper geometry was lowered to the reduced gap. Next, the excess sample that had migrated outside the gap was removed and the upper geometry was further lowered to the measurement position (gap = 0.100 mm). With the measurement position loaded, the temperature of the sample was equilibrated to 50 °C. Finally, once the sample temperature was measured to be stable between 49.90 °C and 50.10 °C, the trigger box (Moeller Easy 412-DC-TC) was activated and the measurement process began using the interface and interconnections provided by the TRIOS software package.

[0171] Measurements: The actual UV-cured RT-DMA measurements were so-called "rapid sampling" measurements performed at 50°C, i.e. oscillatory rapid sampling performed at 50°C for 128 s duration, 1% strain, rotation speed of 52.36 rad / s, and measurement frequency of 50 points / s (i.e. 0.020 s between each successive measurement point).

[0172] Measurements were then initiated via the start button in the TRIOS software. Once data sampling was initiated, the rheometer sent a signal to the control relay, which in turn activated the Omnicure LX500 UV light source to illuminate the respective sample with the aforementioned delay of 1.519 seconds after the start of data sampling. As described above, the samples were illuminated with 385 nm UV light (intensity 60-70 mW / cm) during the 128 seconds of rapid sampling data collection. 2 After the measurements were completed, the TRIOS data files were exported to Microsoft Excel. The samples were then removed and the plate was washed thoroughly with ethanol before loading the next sample.

[0173] Data Analysis: As previously described, TRIOS data was exported to Microsoft Excel. Excel was used to plot graphs and calculate various parameters for characterization of cure speed performance of the test formulations as described below. Graphs included those corresponding to storage modulus (G') as a function of UV-time (UV-time was calculated by subtracting the delay time (1.519 seconds) from the actual time for each individual data point), and relative storage modulus (rel G') as a function of UV-time (rel G' was calculated by the quotient of the G' value measured at a given UV-time and the maximum G' value obtained during the cure measurement). The maximum value observed in the G' graphs was determined by taking the average of the G' values ​​between 110 and 120 seconds and is reported in Tables 3A-3E below in the column headed "Max. G'". For samples that were not fully cured during the test time, this column is denoted with the symbol "NFC" indicating that Max. G' was not achievable given the test procedure and time limits used.

[0174] Meanwhile, the characteristic parameters include (1) the time to reach a 30% total storage modulus (G') increase, and (2) the average G' of 110-120 seconds (the average storage modulus value from six data points toward the end of the cure measurement). The results of (1) for each formulation are shown in Tables 3A-3E below, along with the T 30%, modulus max are reported in a column under the heading: JPEG0007618588000020.jpg248170JPEG0007618588000021.jpg255167JPEG0007618588000022.jpg25516 2JPEG0007618588000023.jpg25596JPEG0007618588000024.jpg255134JPEG0007618588000025.jpg255132

[0175] [Discussion of results] Formulations 1-4 demonstrate that faster modulus build-up can be achieved using compositions according to the present invention. Specifically, compositions (1) containing methacrylate-functional reactive oligomer components and acrylate-functional reactive diluent monomer components exhibit faster modulus build-up (T) than direct analogs using methacrylate / methacrylate (2), acrylate / acrylate (3), and acrylate / methacrylate (4) functional groups in the reactive oligomer and diluent monomer components, respectively. 30%, modulus max (measured as G') and a lower elastic modulus (measured as G').

[0176] Formulation 5 also demonstrates that with the compositions of the present invention, a different, slower reacting reactive diluent monomer component (consisting of EHA) can be used to obtain similar benefits when compared to Formulations 6-8. Formulations 16-25 further demonstrate the benefits of the present invention with respect to different reactive diluent monomers at different amounts.

[0177] Formulations 28-37 demonstrate that the effectiveness of the present invention is not limited to one particular reactive oligomer; that is, similar effects can be obtained using different polyols and isocyanates.

[0178] Formulations 31, 38, and 39 show improved cure speed and / or modulus at various reactive diluent levels, especially when compared to the control formulation 30.

[0179] Formulations 40-44 show that mixtures of different reactive diluents can be used, including those with polymerizable groups other than acrylate groups, such as acrylamides, N-vinylamides, and mixtures thereof. Formulation 45 shows that reactive oligomer components including mixtures of methacrylate and acrylate functional reactive oligomers can also achieve improved performance, especially when compared to the all-acrylate analogue Formulation 3.

[0180] However, Table 3B shows that compositions according to the present invention that include multi-endcapped oligomers also demonstrate one or more technical advantages: Surprisingly, certain multi-endcapped methacrylate-functional oligomers have been shown to have superior cure rate properties over an all-acrylate system (shown as Example 46).

[0181] Furthermore, with respect to Table 3B, it is further shown that mixtures of different reactive diluents in various amounts can be used with positive effects, including those containing polymerizable groups other than acrylate groups (such as Formulations 63 to 67).

[0182] In Table 3C, it is also shown that the benefits of the present invention can potentially be realized by utilizing oligomers that are partially end-capped with non-polymerizable groups such as hydroxyl groups. As an example, Formulation 69 shows the cure rate improving effect that methacrylate-functionalized oligomers have over their acrylate-functionalized analogs, while Formulation 73 further shows that by partially end-capping the oligomer with -OH groups, it is possible to obtain comparable modulus build-up while reducing the G' value. Surprisingly, in contrast to the known inhibitory effect on cure rate observed when reducing the overall functionality of acrylate-functionalized oligomers in this application, no similar effect was observed with methacrylate-functionalized oligomers, such as when the functionality was reduced from about 2 to about 1.5.

[0183] Figures 1 and 2 graphically illustrate the beneficial effects of such formulations. In Figure 1, the relative modulus based on G'max (%) is plotted on the y-axis as a function of time (seconds) on the x-axis for four formulations (68, 69, 70, and 73). Formulations 69 and 73 are shown to achieve significantly faster relative modulus build-up, suggesting easier suitability for faster line processing speeds in optical fiber coating processes. In contrast, formulations 68 and 70, which are not in accordance with the present invention, show relatively poor modulus build-up.

[0184] This relative improvement in modulus build-up rate is particularly surprising in light of the finding that the all-acrylate control formulation 3 achieves a faster nominal cure rate in terms of the % reactive (meth)acrylate unsaturation (%RAU) metric when compared to formulation 1. This phenomenon can be demonstrated in FIG. 2, where the %RAU for each of formulations 68, 69, 70, and 73 is plotted on the y-axis as a function of time (seconds) on the x-axis. The data in the graph was generated by FTIR techniques that are well known in the art to which the present invention applies and are further described in Jansen et al.: Real-Time Infrared Determination of Photoinitiated Copolymerization Reactivity Ratios: Application of the Hilbert Transform and Critical Evaluation of Data Analysis Techniques; Macromolecules 2004, 37, 2275-2286 (2004). As shown in Figure 2, such improved suitability of Formulations 69 and 73 is particularly surprising when looking at cure speed as a function of the %RAU metric (same format and measurements as in Figure 2), because Formulations 68 and 70 appear faster by the %RAU metric alone.

[0185] In Table 3D, formulations 79-82 show the improved cure speed effect of methacrylate functionalized oligomers versus acrylate functionalized oligomers, as well as a slight improvement in modulus (see 81 vs. 79 and 31 vs. 30). This effect is also seen when the functional groups appear along the oligomer backbone as well as as terminal groups (see 82 vs. 80). In fact, the reactive oligomer with methacrylate functional end groups and backbone groups had the fastest cure speed of all of the series (82). Furthermore, it is noteworthy that formulation 80 (with methacrylate functionality along the backbone and acrylate groups at the terminal groups) was also fast curing, especially when compared to the all-acrylate analog (79). This indicates that the effect of the present invention can be realized even at relatively low mole fractions of methacrylate groups present in the reactive oligomer component.

[0186] Formulations 83-93 further demonstrate the generally improved effectiveness of the compositions of the present invention. Comparing analogs 83, 84, 85, and 90, it is clear that for a given reactive diluent, methacrylate functionalization along either the backbone or end groups of the oligomer is an improvement over pure acrylate functionalization (end groups in 84 and end groups in 85 vs. 83), and that methacrylate functionalization along both the backbone and end groups of the oligomer can induce the fastest improvement in modulus build-up of all (T 30%, modulus max It has been demonstrated that the value is 90<85<84<83).

[0187] Formulations 86-93 demonstrate that methacrylate functionality, when placed along either the oligomer backbone or end groups, provides improved cure rates over the pure acrylate-functionalized oligomer (86), even with different types, mixtures, and amounts of reactive diluent components.

[0188] Additional Exemplary Embodiments The following additional exemplary embodiments are meant to further illustrate various potential aspects of the present invention. The present invention is not intended to be limited to any embodiment described herein, and various combinations and / or variations of the following can be readily contemplated.

[0189] A first aspect of a first additional exemplary embodiment is A reactive oligomer comprising one or more polymerizable groups; wherein at least one of the polymerizable groups is a methacrylate group; a reactive diluent monomer comprising a polymerizable group capable of (co)polymerizing with the polymerizable group of the reactive oligomer; wherein at least one polymerizable group of the reactive diluent monomer is an acrylate group, an acrylamide group, or an N-vinylamide group; a photoinitiator component; and In some cases, additive ingredients A radiation curable composition comprising:

[0190] Another aspect of the first additional exemplary embodiment is that the composition comprises a reactive oligomer component consisting of a reactive oligomer; and The composition of the first aspect includes a reactive diluent monomer component consisting of a reactive diluent monomer.

[0191] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects of the first additional exemplary embodiment, wherein the reactive oligomer component comprises, consists essentially of, or consists of a reactive urethane oligomer.

[0192] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects of the first additional exemplary embodiment, wherein the reactive diluent monomer component comprises, consists of, or consists essentially of a monofunctional acrylate monomer.

[0193] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects of the first additional exemplary embodiment, wherein the molar ratio of methacrylate groups present in the total composition to the total amount of polymerizable groups present in the total composition is from 2% to 20%, or from 2% to 18%, or from 2% to 15%, or from 3% to 18%, or from 4% to 20%, or from 4% to 18%, or from 2% to 16%, or from 4% to 15%, or from 5% to 15%, or from 5% to 12%, or from 9% to 20%, or from 9% to 18%, or from 9% to 15%.

[0194] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80%, or at least 90% of the mole fraction of polymerizable groups in the reactive oligomer or reactive oligomer component consists of methacrylate groups.

[0195] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the mole fraction of polymerizable groups is determined by the mole fraction calculation method described elsewhere herein using the Mn,theo value.

[0196] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the mole fraction of polymerizable groups is determined by the mole fraction calculation method described elsewhere herein using the Mn value.

[0197] Another aspect of the first additional exemplary embodiment is the composition of the previous aspect, wherein the Mn value is determined according to the SEC method using a triple detector array as described elsewhere herein.

[0198] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the polymerizable groups in the reactive oligomer component consist of, or consist essentially of, methacrylate groups.

[0199] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the polymerizable groups in the reactive oligomer component comprise, consist of, or consist essentially of polymerizable end groups.

[0200] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the polymerizable group in the reactive oligomer component comprises, consists of, or consists essentially of a polymerizable backbone group.

[0201] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the at least one reactive oligomer comprising a polymerizable group is a reaction product of a polyol compound, a diisocyanate compound, a hydroxyl-functional compound having at least one methacryloyl group, and, optionally, a compound having at least one hydroxyl group and no polymerizable group.

[0202] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the hydroxyl-functional compound having at least one methacryloyl group contains two methacryloyl groups.

[0203] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive oligomer component comprises a mono-, di-, tri-, tetra-, or penta-functional reactive oligomer, or a combination thereof.

[0204] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein at least 50%, or at least 60%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99% of the mole fraction of the polymerizable groups in the reactive diluent monomer component are acrylate groups, acrylamide groups, or N-vinylamide groups.

[0205] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein at least 50%, or at least 60%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99% of the mole fraction of the polymerizable groups in the reactive diluent monomer component consists of acrylate groups.

[0206] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the mole fraction of polymerizable groups is determined by the mole fraction calculation method described elsewhere herein using the Mn,theo value.

[0207] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the mole fraction of polymerizable groups is determined by the mole fraction calculation method described elsewhere herein using the Mn value.

[0208] Another aspect of the first additional exemplary embodiment is the composition of the previous aspect, wherein the Mn value is determined according to the SEC method using a triple detector array as described elsewhere herein.

[0209] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive oligomer has a theoretical molecular weight (Mn,theo) greater than 2000 g / mol, or greater than 4000 g / mol, or greater than 5000 g / mol.

[0210] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive oligomer and / or reactive oligomer component has a number average molecular weight (Mn) of greater than 2000 g / mol, greater than 4000 g / mol, or greater than 5000 g / mol, or greater than 6000 g / mol, or greater than 9000 g / mol, or from 2000 g / mol to 30000 g / mol, or from 2000 g / mol to 20000 g / mol, or from 4000 g / mol to 30000 g / mol, or from 4000 g / mol to 20000 g / mol, or from 6000 g / mol to 20000 g / mol.

[0211] Another aspect of the first additional exemplary embodiment is the composition of the previous aspect, wherein Mn is determined according to the SEC method using a triple detector array as described elsewhere herein.

[0212] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive diluent monomer component comprises, consists of, or consists essentially of reactive monomers having an Mn, theo or Mn of 86 g / mol to 800 g / mol, or 100 g / mol to 350 g / mol.

[0213] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive diluent monomer comprises, consists of, or consists essentially of a monofunctional monomer.

[0214] Another aspect of the first additional exemplary embodiment is a composition comprising, based on the total weight of the composition: the reactive oligomeric component is present in an amount of from 20% to 95% by weight, or from 40% to 80% by weight; the reactive diluent monomer component is present in an amount of from 4 wt% to 75 wt%, or from 20 wt% to 50 wt%; The photoinitiator is present in an amount of 0.25% to 7% by weight, or 0.5% to 3% by weight, or 1% to 7% by weight; and The composition of any of the previous aspects, wherein the additive is present in an amount of from 0 wt % to 50 wt %.

[0215] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the additive comprises an adhesion promoter.

[0216] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the adhesion promoter comprises one or more of gamma-mercaptopropyltrimethoxysilane, trimethoxysilylpropyl acrylate, tetraethoxysilane, or 3-trimethoxysilylpropane-1-thiol.

[0217] Another aspect of the first additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive oligomer comprises a silane coupling group.

[0218] A first aspect of the second additional exemplary embodiment is a copolymerization method comprising: a reactive oligomer; a reactive diluent monomer; an initiator; and, optionally, an additive; wherein the reactive oligomer is a reaction product of a compound having a polymerizable group; and a copolymerization method between the compound having at least one polymerizable group and 2-hydroxyethyl acrylate (HEA) that results in a self-reactivity ratio (RR 1 ) is at least 1, or at least 1.3, or at least 1.4, or between 1 and 5, or between 1.4 and 3.5, or between 1.2 and 1.7.

[0219] An additional aspect of the second additional exemplary embodiment is the reactivity ratio (RR 2 ) is from 0.1 to 0.5, or from 0.1 to 0.4, or from about 0.15 to about 0.35.

[0220] An additional aspect of the second additional exemplary embodiment is 1 and R.R. 2 is determined according to a multivariate analysis using an infrared spectrum of the copolymer input compound, the radiation curable composition of any of the aspects of the second additional exemplary embodiment.

[0221] An additional aspect of the second additional exemplary embodiment is 1 / RR 2 is greater than 1, or greater than 3, or greater than 5, or greater than 8, or from 2 to 12, or from 3 to 11, or from 10 to 12.

[0222] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the reactive oligomer is a urethane oligomer, the urethane oligomer being a reaction product of a polyol compound, a diisocyanate compound, and a hydroxyl functional compound having a reactive group.

[0223] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the hydroxyl functional compound having at least one reactive group comprises 2-hydroxyethyl (meth)acrylate, caprolactone 2-(methacryloyloxy)ethyl ester, glycerol mono(meth)acrylate, glycerol acrylate methacrylate, or glycerol dimethacrylate.

[0224] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the reactive diluent monomer comprises, consists of, or consists essentially of 2-ethylhexyl acrylate, 2-phenoxyethyl acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, N-vinylpyrrolidone, acryloylmorpholine, dimethylacryl-amide, N-vinylcaprolactam, ethoxylated 2-phenoxyethyl acrylate, 4-hydroxybutyl acrylate, lauryl acrylate, isobornyl acrylate, caprolactone acrylate, isodecyl acrylate, or ethoxylated nonylphenol acrylate, or mixtures thereof.

[0225] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the initiator comprises, consists of, or consists essentially of a photoinitiator.

[0226] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the additive comprises an adhesion promoter.

[0227] Another aspect of the second additional exemplary embodiment is the composition of any of the previous aspects, wherein the adhesion promoter comprises one or more of gamma-mercaptopropyltrimethoxysilane, trimethoxysilylpropyl acrylate, tetraethoxysilane, or 3-trimethoxysilylpropane-1-thiol.

[0228] Another aspect of the second additional exemplary embodiment is the composition of any of the previous aspects, wherein the reactive oligomer comprises a silane coupling group.

[0229] An additional aspect of the second additional exemplary embodiment is the radiation curable composition of any of the aspects of the second additional exemplary embodiment, wherein the additive comprises an antioxidant, a polymerization inhibitor, a photosensitizer, a carrier surfactant, a tackifier, a catalyst, a stabilizer, a surface agent, and / or an optical brightener.

[0230] A first aspect of the third additional exemplary embodiment is a method for coating an optical fiber, comprising: providing a glass optical fiber; applying a coating composition onto a surface of the glass optical fiber; and applying a dose of ultraviolet light to cure the coating composition, wherein the coating composition is a composition according to any of the aspects of the first additional exemplary embodiment or the second additional exemplary embodiment.

[0231] A first aspect of the fourth additional exemplary embodiment is a coated optical fiber coated with a cured product of a composition according to any of the aspects of the first additional exemplary embodiment or the second additional exemplary embodiment.

[0232] Unless otherwise specified, the term wt. % refers to the amount by weight of a particular component relative to the total liquid radiation curable composition in which it is incorporated.

[0233] The use of the terms "a" and "an" and "the" and similar referents in the context of describing the present invention (particularly in the context of the claims that follow) should be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" should be construed as open-ended terms (i.e., meaning "including, but not limited to"), unless otherwise indicated. The recitation of ranges of values ​​herein is merely intended to be a shorthand method of referring individually to each individual value falling within the range, unless otherwise indicated herein, and each individual value is incorporated into the specification as if it were individually set forth herein. All methods described herein can be performed in any suitable order, unless otherwise indicated herein or clearly contradicted by context. The use of any and all examples or exemplary language (e.g., "etc.") provided herein is intended merely to further clarify the invention, and does not limit the scope of the invention, unless otherwise stated in the claims. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0234] Preferred embodiments of the invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect such variations to be employed by those of ordinary skill in the art as appropriate, and the inventors intend the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

[0235] While the present invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as set forth in the claims.

Claims

1. a reactive oligomer component comprising or consisting of at least one reactive oligomer containing a polymerizable group; A reactive oligomeric component, wherein at least 20%, or at least 30%, of the molar fraction of polymerizable groups in the reactive oligomeric component consists of methacrylate groups; The reactive urethane oligomer has a theoretical molecular weight (Mn,theo) of greater than 2000 g / mol; a reactive diluent monomer component comprising or consisting of a reactive diluent monomer having at least one polymerizable group capable of (co)polymerizing with a polymerizable group of the reactive oligomer component, comprising a monofunctional acrylate monomer, a reactive diluent monomer component, wherein at least 50%, or at least 80%, or at least 90%, or at least 95%, or at least 98%, or at least 99% of the mole fraction of the polymerizable groups of the reactive diluent monomer component are acrylate groups, acrylamide groups, N-vinylamide groups, or mixtures thereof; and Photoinitiator Component Including, The reactive oligomer is Polyol compound; Diisocyanate compounds; a hydroxyl-functional compound having at least one methacryloyl group; and Compounds that have a hydroxyl group and no polymerizable group comprising the reaction product of the molar ratio of methacrylate groups present in the entire composition to the total amount of polymerizable groups present in the entire composition is from 2% to 20%; Radiation curable compositions for coating optical fibers.

2. 2. The radiation curable composition of claim 1, wherein the reactive oligomer has a theoretical molecular weight (Mn,theo) greater than 2000 g / mol, or greater than 4000 g / mol, or greater than 5000 g / mol.

3. 3. The radiation curable composition according to claim 1 or 2, wherein the reactive oligomer and / or reactive oligomer component has a number average molecular weight (Mn) of more than 2000 g / mol, or more than 4000 g / mol, or more than 5000 g / mol, or more than 6000 g / mol, or more than 9000 g / mol, or from 2000 g / mol to 30000 g / mol, or from 2000 g / mol to 20000 g / mol, or from 4000 g / mol to 30000 g / mol, or from 4000 g / mol to 20000 g / mol, or from 6000 g / mol to 20000 g / mol; wherein Mn is determined according to a SEC method using a triple detector array.

4. 4. The radiation curable composition according to claim 1 , wherein the reactive diluent monomer component comprises or consists of a monofunctional acrylate monomer having a Mn, theo or Mn of 86 g / mol to 800 g / mol, or 100 g / mol to 350 g / mol, or 86 g / mol to 150 g / mol.

5. 5. The radiation curable composition of claim 1, wherein the reactive oligomer comprises a silane coupling group.

6. 6. The radiation curable composition of claim 1, wherein the hydroxyl functional compound having at least one methacryloyl group contains two or more methacryloyl groups.

7. 7. The radiation curable composition of claim 6, wherein the hydroxyl functional compound having two or more methacryloyl groups comprises 1,2-glycerol dimethacrylate, 1,3-glycerol dimethacrylate, or a combination thereof.

8. 8. The radiation curable composition according to claim 1 , wherein the reactive oligomer is terminated at least at one end with a hydroxyl functional end group; and / or the reactive oligomer component comprises or consists of a monofunctional reactive oligomer.

9. The radiation curable composition of claim 8, wherein the hydroxyl functional end group is a reaction product of 2-ethylhexanol.

10. 10. The radiation curable composition of claim 1, wherein the hydroxyl functional compound having at least one methacryloyl group comprises 2-hydroxyethyl methacrylate, caprolactone 2-(methacryloyloxy)ethyl ester, or glycerol monomethacrylate, or a combination thereof.

11. 11. The radiation curable composition according to claim 1, wherein the molar fraction of the polymerizable groups of the reactive oligomer component is at least 60%, or at least 70%, or at least 80%, or at least 90% consists of methacrylate groups.

12. The polymerizable group of the reactive oligomer component comprises a methacrylate group; and / or 12. A radiation curable composition according to claim 1, wherein the polymerizable groups of the reactive diluent monomer component comprise acrylate groups.

13. 13. The radiation curable composition according to any one of claims 1 to 12, wherein the molar ratio of methacrylate groups present in the total composition to the total amount of polymerizable groups present in the total composition is from 2% to 18%, or from 2% to 15%, or from 3% to 18%, or from 4% to 20%, or from 4% to 18%, or from 2% to 16%, or from 4% to 15%, or from 5% to 15%, or from 5% to 12%, or from 9% to 20%, or from 9% to 18%, or from 9% to 15%.

14. 14. A radiation curable composition according to any one of claims 1 to 13, wherein the molar ratio of acrylate groups to methacrylate groups in the total composition is from 4:1 to 50:1, or from 4:1 to 25:1, or from 4:1 to 10:1, or from 4.6:1 to 50:1, or from 4.6:1 to 25:1, or from 4.6:1 to 10:1, or from 5.6:1 to 50:1, or from 5.6:1 to 25:1, or from 5.6:1 to 10:

1.

15. based on the total weight of the composition, the reactive oligomeric component is present in an amount of from 20% to 95% by weight, or from 40% to 80% by weight; the reactive diluent monomer component is present in an amount of from 4 wt% to 75 wt%, or from 20 wt% to 50 wt%; the photoinitiator is present in an amount of 0.25% to 7% by weight, or 0.5% to 3% by weight, or 1% to 7% by weight; and 15. The radiation curable composition of claim 1, wherein the additive is present in an amount of from 0% to 50% by weight.

16. The following conditions (a), (b), (c), or (d): (a) the polyol compound comprises or consists of a polyether, polyester, polycarbonate, polyamide, polycaprolactone, or acrylic moiety; (b) the diisocyanate compound comprises or consists of isophorone diisocyanate, 2,4-isomeric toluene diisocyanates, 2,4- and / or 4,4'-methylene dicyclohexyl diisocyanate, methylene diphenyl diisocyanate, tetramethyl xylene diisocyanate, (hydrogenated) xylylene diisocyanate, 1,5-pentane diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate, 2,4,4-trimethyl-hexamethylene diisocyanate, or hexamethylene diisocyanate, or combinations thereof; and / or (c) the hydroxyl-functional compound having at least one methacryloyl group is a methacrylate compound and comprises or consists of 2-hydroxyethyl methacrylate, caprolactone 2-(methacryloyloxy)ethyl ester, or a combination thereof; (d) The compound having a hydroxyl group and no polymerizable group includes or consists of n-butanol, 2-ethylhexanol, benzyl alcohol, or a combination thereof.

16. The radiation curable composition according to claim 1 , wherein at least one of the following is applied:

17. 17. The radiation curable composition of any one of claims 1 to 16, wherein the reactive diluent monomer component comprises or consists of 2-ethylhexyl acrylate, 2-phenoxyethyl acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, N-vinylpyrrolidone, acryloylmorpholine, dimethylacrylamide, N-vinylcaprolactam, ethoxylated 2-phenoxyethyl acrylate, 4-hydroxybutyl acrylate, lauryl acrylate, isobornyl acrylate, caprolactone acrylate, isodecyl acrylate, or ethoxylated nonylphenol acrylate, or mixtures thereof.

18. The photoinitiator may be 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, dimethoxybenzophenone, 1-hydroxycyclohexyl phenyl ketone, phenyl(1-hydroxyisopropyl)ketone, 2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone, and 4-isopropylphenyl(1-hydroxyisopropyl)ketone, benzil dimethyl ketal, oligo-[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone]; 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenyl, bis(2,4,6-trimethylbenzoyl)phenyl, 18. The radiation curable composition according to claim 1, which comprises or consists of: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropanone-1, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 4-benzoyl-4'-methyldiphenylsulfide, 4,4'-bis(diethylamino)benzophenone, or 4,4'-bis(N,N-dimethylamino)benzophenone (Michler's ketone).

19. 19. The radiation curable composition of claim 1, wherein the additive comprises an adhesion promoter.

20. 20. The radiation curable composition of claim 19, wherein the adhesion promoter comprises mercaptopropyltrimethoxysilane, trimethoxysilylpropyl acrylate, tetraethoxysilane, or 3-trimethoxysilylpropane-1-thiol.

21. 21. The radiation curable composition of claim 1, wherein the additives comprise antioxidants, polymerization inhibitors, photosensitizers, carrier surfactants, tackifiers, catalysts, stabilizers, surface agents, and / or optical brighteners.

22. The composition has a T of less than 2 seconds, or less than 1.5 seconds, or less than 1.25 seconds, or less than 1.00 seconds, or from 0.3 to 2 seconds, or from 0.3 to 1.5 seconds, or from 0.3 to 1.25 seconds, or from 0.3 to 1.00 seconds. ３０％，ｍｏｄｕｌｕｓ ｍａｘ where T ３０％，ｍｏｄｕｌｕｓ ｍａｘ The value is measured by the procedures described herein, and / or 22. The radiation curable composition of any one of claims 1 to 21, wherein the composition has a maximum elastic modulus (G') value of less than 0.65 MPa, or less than 0.5 MPa, or less than 0.25 MPa, or from 0.10 to 1 MPa, or from 0.10 to 0.65 MPa, or from 0.10 to 0.5 MPa, or from 0.10 to 0.25 MPa, wherein the G' value is measured by the procedure described herein.

23. The copolymerization between the hydroxyl functional compound having at least one methacryloyl group and 2-hydroxyethyl acrylate (HEA), The self-reactivity ratio (R １ ) is at least 1, or at least 1.3, or at least 1.4, or between 1 and 5, or between 1.4 and 3.5, or between 1.2 and 1.7; And the reactivity ratio of the compound having at least one methacryloyl group to HEA (R ２ ) is from 0.1 to 0.5, or from 0.1 to 0.4, or from 0.15 to 0.35; Here, R １ and R ２ 23. The radiation curable composition according to claim 1, wherein is determined according to a multivariate analysis using infrared spectra of the copolymer input compounds.

24. R １ / R ２ 24. The radiation curable composition of claim 23, wherein is greater than 1, or greater than 3, or greater than 5, or greater than 8, or from 2 to 12, or from 3 to 11, or from 10 to 12.

25. 1. A method for coating an optical fiber, comprising the steps of: providing a glass optical fiber; applying a primary coating composition to a surface of the glass optical fiber; applying a secondary coating composition to the primary coating composition; exposing the primary coating composition and the secondary coating composition to at least one radiation source capable of emitting ultraviolet radiation to affect curing of the primary coating composition and the secondary coating composition to form a cured primary coating on the surface of the optical fiber and a cured secondary coating on the surface of the cured primary coating; 25. The method of claim 1 , wherein the primary coating composition is a composition according to any one of claims 1 to 24.

26. A method for coating an optical fiber, comprising the steps of: providing a glass optical fiber; applying a primary coating composition to a surface of the glass optical fiber; providing UV light in an amount sufficient to at least partially cure said primary coating composition; applying a secondary coating composition to the primary coating composition; exposing the primary coating composition and the secondary coating composition to at least one radiation source capable of emitting ultraviolet radiation to affect curing of the primary coating composition and the secondary coating composition to form a cured primary coating on the surface of the optical fiber and a cured secondary coating on the surface of the cured primary coating; 25. The method of claim 1 , wherein the primary coating composition is a composition according to any one of claims 1 to 24.

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