JP7050089B2 - How to apply coating liquid to optical fiber - Google Patents

Description

priority

This application claims the benefit of priority under US Provisional Application No. 62 / 489,123 filed April 24, 2017, Dutch Patent Application No. 2017098 filed June 20, 2017. Incorporate herein by claiming the benefit of priority under, relying on its content and referencing its entire content.

The present specification relates to a method of coating an optical fiber. More specifically, the present specification relates to a method of applying a coating liquid to an optical fiber.

The transmittance of light through an optical fiber is highly dependent on the properties of the coating applied to the fiber. The coating usually comprises a primary coating and a secondary coating, where the secondary coating surrounds the primary coating and the primary coating contacts the glass waveguide (core + clad) portion of the fiber. The secondary coating is a harder (higher Young's modulus) material than the primary coating and is designed to protect the glass waveguide from wear or damage caused by external forces during fiber processing and handling. The primary coating is a softer (Lower Young's modulus) material and is designed to buffer or dissipate the resulting stress from the forces applied to the outer surface of the secondary coating. Dissipation of stress in the primary layer attenuates the stress and minimizes the stress reaching the glass waveguide. The primary coating is especially important for dissipating the stress generated when the fiber is bent. Since bending stress creates local perturbations in the index profile of the glass waveguide, the bending stress transmitted to the glass waveguide on the fiber should be minimized. Due to the local index of refraction perturbation, the intensity of the light passing through the waveguide is lost. By dissipating stress, the primary coating minimizes strength loss due to bending.

A coating solution commonly used in the manufacture of optical fibers is an acrylate-based composition that can be cured by heat or exposure to ultraviolet (UV) rays. The coating liquid is applied to the surface of the fiber in a liquid state and then exposed to heat or UV light for curing. The coating liquid can be applied to one or more layers, and in many cases a two-layer coating system (primary + secondary) is the preferred embodiment. The primary coating is applied directly to the surface of the fiber and the secondary coating is applied on top of the primary coating.

In a typical fiber optic drawing process, the fibers are continuously drawn from the glass preform at a particular drawing rate. The glass preform comprises a central region having the desired core composition for the drawn fiber and one or more annular regions around it having the desired composition for one or more clad regions of the drawn optical fiber. The preform is placed in a drawing furnace and heated sufficiently to soften the glass. The action of gravity or the tensile force driven by the capstan causes the glass to stretch from the softened portion of the preform. As the glass stretches, it becomes thinner and forms fibers. The diameter of the fiber is controlled, the fiber is cooled and then guided to a coating unit for applying one or more coating solutions. The coating liquid cures to form a solid coating, and the coated fibers are taken up and wound up on a spool. The path that the fiber crosses as it travels from the drawing furnace to the spool is called the process path.

There is a continuing need to reduce the cost of fiber optic manufacturing by increasing the drawing speed. However, as the drawing speed increases, it becomes more difficult to apply and cure the coating solution. In particular, it becomes more difficult to achieve a uniform thickness coating over the length and perimeter of the fiber. Uniform thickness of the coating is required to facilitate the connection and joining of the coated fibers and to attach the connector to the ends of the coated fibers. Currently, there is a demand for a coating process capable of forming a coating of uniform thickness on glass fiber in a continuous high-speed drawing process.

The method of applying the coating liquid to the optical fiber is described. The optical fiber is drawn through the guide die into the coating chamber and through the coating chamber to the sizing die. The coating chamber contains a coating solution. The method comprises guiding the coating liquid in the coating chamber in a direction across the processing path of the optical fiber. The transverse flow of the coating liquid counteracts the harmful effects associated with the gyre formed in the coating chamber during the drawing process. Benefits of transverse flow include removal of air bubbles, lowering of vortex temperature, improved wetting, homogenization of coating liquid properties in the coating chamber, and stabilization of the meniscus.

The present specification extends to:
A method of processing optical fiber, which is as follows:
A step of drawing an optical fiber in a drawing direction along a process path through a coating chamber containing a coating liquid for coating the optical fiber.
A step of guiding a separate flow of coating fluid through the coating chamber in a direction across the drawing direction, the separate flow of coating liquid crossing the process path in the drawing direction, passing through and / or rotating . And a method comprising a step of mixing, diluting, or thermally or mechanically interacting with the coating solution contained in the coating chamber.

The present specification extends to:
It ’s a method of processing optical fiber.
The step of drawing the optical fiber through the guide die into the pressure coating chamber containing the first coating liquid at the drawing speed,
The step of forming the meniscus of the first coating liquid on the optical fiber in the pressure coating chamber, and
A step of forming a boundary layer on the optical fiber in the pressure coating chamber, wherein the boundary layer contains the first coating liquid, begins with the meniscus, and the boundary layer is from the guide die. With steps, with a thickness that increases with increasing distance,
In the step of drawing the optical fiber through the pressure coating chamber to the sizing die at the drawing speed, the sizing die causes the boundary layer to shrink, and the shrinkage occurs from the boundary layer to the pressure coating chamber. A step that causes the release of the first coating solution to and the formation of a vortex containing the first coating solution in the pressure coating chamber.
A step of drawing the optical fiber through the sizing die at the drawing speed, wherein the optical fiber exits the sizing die at the surface layer of the first coating liquid.
A method comprising the step of laterally flowing the first coating liquid in the coating chamber through a channel disposed between the guide die and the sizing die.

The present specification extends to:
A method of processing optical fiber, which is as follows:
A step of drawing an optical fiber in a drawing direction along a process path through a coating chamber containing a coating liquid to coat the optical fiber.
A step that guides a separate flow or flow of coating fluid through the coating chamber in a direction that crosses the drawing direction of the optical fiber through the coating chamber, where the transverse flow of coating liquid crosses the process path in the drawing direction. A method comprising, stepping through , and / or rotating , mixing, diluting, or thermally or mechanically interacting with a coating solution contained in a coating chamber.

The present specification extends to:
A system for processing optical fibers
One or more coating chambers with fiber inlets and fiber outlets to hold the coating liquid for coating the optical fiber.
An inlet for delivering a flow or flow of coating fluid to the coating chamber,
It is equipped with an outlet for removing the coating liquid from the coating chamber, and the inlet and the outlet are different from the fiber inlet and the fiber outlet, and the inlet has a flow or flow of the coating liquid in a direction crossing the drawing direction of the optical fiber through the coating chamber. A system that is configured to send.

Additional features and advantages are described in the detailed description below, some of which will be readily apparent to those skilled in the art, or the specification and its claims, as well as the accompanying drawings. Will be recognized by implementing the embodiments described in.

It should be understood that the general description above and the detailed description below are merely examples and are intended to provide an outline or framework for understanding the nature and characteristics of the claims.

The accompanying drawings are included to provide further understanding and are incorporated herein by them. The drawings illustrate selected embodiments of the specification and, together with the specification, serve to illustrate the principles and operations of the methods, products and compositions contained herein. The features shown in the drawings are illustrations of selected embodiments herein and are not necessarily depicted to the appropriate scale.

The specification concludes with a claim that specifically points out and explicitly claims the subject matter of the description, which is believed to be better understood from the following description in conjunction with the accompanying drawings.
It is a figure which shows the calculated boundary layer of the coating liquid on an optical fiber. It is a figure which shows the conventional design of a sizing die. It is a figure which shows the design of only the cone of a sizing die. FIG. 6 shows a calculated temperature profile of a vortex formed by a sizing die with a conventional design. FIG. 6 shows a calculated temperature profile of a vortex formed by a sizing die with a cone-only design. It is a figure which shows the lateral flow of the coating liquid in the coating chamber operably connected to the sizing die which has a conventional design. It is a figure which shows the lateral flow of the coating liquid in a pressure coating chamber operably connected to a cone-only sizing die. It is a figure which shows the lateral flow of the coating liquid through the channel in the pressure coating chamber arranged between the guide die and the sizing die. It is a figure which shows the coating unit which provided the pressure coating chamber for applying a primary coating liquid and a secondary coating liquid to an optical fiber. It is a figure which shows the coating unit which provided the pressure coating chamber for applying a primary coating liquid and a secondary coating liquid to an optical fiber.

The embodiments described in the drawings are merely exemplary and are not intended to limit the scope of the detailed description or claims. Whenever possible, use the same reference number throughout the drawing to refer to the same or similar features.

The present disclosure is provided as a feasible teaching and can be more easily understood by reference to the following description, drawings, examples and claims. To this end, one of ordinary skill in the art will recognize and understand that many modifications can be made to the various aspects of the embodiments described herein, with beneficial results. It will also be clear that some of the desired benefits of this embodiment can be obtained by selecting some of the features without utilizing other features. Accordingly, one of ordinary skill in the art will recognize that many modifications and indications are possible and may even be desirable in certain circumstances and are part of this disclosure. Therefore, it should be understood that this disclosure is not limited to the particular compositions, articles, devices and methods disclosed, unless otherwise stated. It should also be understood that the terms used herein are intended to describe only certain aspects and are not intended to be limiting.

The present specification refers to methods and processes for forming optical fibers. In a continuous optical fiber manufacturing process, the optical fiber is drawn from a heated preform placed in a drawing furnace and passed through a series of processing stages. The processing steps typically include a measuring unit (eg, fiber diameter control) to evaluate the quality and other characteristics of the optical fiber, a heating step, a cooling state, a primary coating step, a secondary coating step, and an ink. It includes a layering step, one or more curing steps to cure the coating or ink layering solution applied to the fiber, and a spool or other winding step to receive and store the coated optical fiber. .. The path that an optical fiber traverses as it advances from the drawing furnace through one or more process units to the winding stage is referred to herein as the optical fiber process path. The process path may be straight or include bends.

The relative position of one process unit along a process path to another is described herein as upstream or downstream. The upstream direction of the process path is the direction toward the preform, and the downstream direction of the process path is the direction toward the winding stage. The location or processing unit upstream of the reference position or processing unit is closer to the preform along the process path than the reference position or processing unit. The process unit located near the drawing furnace along the process path is said to be upstream of the process unit located further away from the drawing furnace along the process path. The drawing furnace is upstream of all other process units and the take-up spool (or take-up stage or other terminal unit) is downstream of all other process units. As an example, the process path of an optical fiber in an exemplary drawing process extends from a drawing furnace to a cooling unit, from a cooling unit to a coating application unit, from a coating application unit to a coating curing unit, and from a coating curing unit to a take-up spool. In the context of the terminology used herein, the drawing furnace is upstream of the cooling unit, the cooling unit is upstream of the coating application unit, the coating application unit is upstream of the coating curing unit, and the coating curing unit is winding. It is located upstream of the take-up spool. Similarly, the take-up spool is downstream of the coating curing unit, the coating curing unit is downstream of the coating application unit, the coating application unit is downstream of the cooling unit, and the cooling unit is downstream of the drawing furnace.

The present specification provides a method of applying a coating liquid to an optical fiber. Using this method, the coating liquid is applied to the glass fiber, the coating liquid is applied to another coating liquid, or the coating liquid is applied to the cured coating. The method involves guiding the optical fiber along the process path, which involves passing the optical fiber through a coating application unit. The coating application unit includes a guide die, a pressure coating chamber, and a sizing die. The pressure coating chamber contains a coating solution used to coat optical fibers. The guide die is upstream of the pressure coating chamber, upstream of the sizing die. The optical fiber enters the pressure coating chamber through the guide die, reaches the sizing die through the pressure coating chamber, and reaches the downstream unit of the fiber drawing process through the sizing die.

This method enables a high speed drawing process for manufacturing optical fibers. Currently, the drawing speed is limited by two problems. That is, (1) it is difficult to wet the optical fiber with the coating liquid when the optical fiber leaves the guide die and enters the coating chamber, and (2) inside the coating chamber near the sizing die when the optical fiber leaves the coating chamber. There are two points that increase the severity of the effects related to the vortex formed by. This method can address both problems and increase the drawing speed while minimizing coating defects. The drawing speeds available in the current method range from at least 30 m / s, or at least 40 m / s, or at least 50 m / s, or at least 60 m / s, or at least 70 m / s, or 30 m / s to 90 m / s. , Or in the range of 40 m / s to 80 m / s.

As the fiber exits the guide die and enters the coating chamber, the fiber comes into contact with the coating liquid. When the fibers get wet, a meniscus of coating liquid is formed on the fibers adjacent to the outlet of the guide die. The coating liquid is accompanied by the fiber as it travels along the process path to the sizing die. The fiber exits the sizing die with a layer of coating liquid attached and is guided along the process path to a downstream processing unit (eg, another coating or curing unit). The thickness of the coating liquid applied to the fiber is determined by the shape of the sizing die, the viscosity of the coating liquid, the temperature of the fiber and the drawing speed. The diameter of the outlet of the sizing die is particularly important in establishing the thickness of the coating liquid applied to the fiber.

For successful coating and uniform coating thickness, effective wetting of the fibers with the coating liquid is required as the fibers enter the coating chamber. The perimeter of the fiber as it passes through the guide die is gas (eg, air, CO ₂ , He). The movement of the fiber around the gas forms a gas boundary layer on the surface of the fiber as it passes through the guide die. The gas boundary layer remains with the fibers as it exits the guide die and enters the coating chamber.

Wetting refers to the process of moving the gas boundary layer with the coating liquid as the fibers come into contact with the coating liquid and pass through the coating liquid. When the fibers are properly wetted with the coating liquid, a meniscus of the coating liquid is formed at the interface between the fiber surface near the outlet of the guide die and the coating liquid, and when the optical fiber is transported toward the outlet of the sizing die, the coating liquid is formed. Boundary layer is formed on the fiber from the tip of the meniscus.

If the coating does not wet the fiber, a gas boundary layer remains on the fiber. This results in the entrainment of gas in the coating chamber and the mixing of gas in the coating liquid. When gas is present in the coating liquid, bubbles are formed in the coating liquid, and the coating liquid applied to the fiber contains bubbles. Bubbles destabilize the meniscus and result in non-uniformity in the coating of the coating on the surface of the fiber. As the coating liquid cures downstream of the sizing die, air bubbles trapped in the coating liquid attached to the fibers remain in the coating. Bubbles in the cured coating impair fiber performance and become defects that promote exfoliation of the cured coating. The presence of air bubbles in the coating chamber also makes it difficult to center and stabilize the fibers as they pass through the coating application unit, which further contributes to the non-uniformity of the coating thickness.

As the drawing speed increases, the force required to move the gas boundary layer increases. In this method, sufficient force is achieved by the pressure coating chamber to move the gas boundary layer and wet the fibers at high drawing speeds. By increasing the pressure of the coating liquid in the coating chamber, it is possible to utilize greater force to apply the coating liquid to the fiber, and the consistent wetting of the fiber at the drawing speed disclosed herein. Be maintained. Pressurization of the coating chamber can be achieved by equipping the coating chamber with a pressure transducer and using the pressure transducer to control the pressure in the coating chamber. In one embodiment, the flow of coating liquid delivered to the coating chamber is supplied from a pressurizing source. By increasing the pressure in the coating chamber, it becomes possible to overcome the pressure associated with the gas phase boundary layer and achieve wetting as the pressure of the coating liquid in the coating chamber increases and the drawing speed increases. ..

As used herein, pressure coating chamber refers to a coating chamber with a pressure above 0 psig (0 kPaG). In various embodiments, the pressure in the pressure coating chamber is at least 0.10 psig (about 690 PaG), or at least 0.50 psig (about 3.4 kPaG), or at least 1.0 psig (about 6.9 kPaG), or at least 5. .0 psig (about 34 kPaG), or at least 10 psig (about 69 kPaG), or at least 25 psig (about 172 kPaG), or at least 50 psig (about 345 kPaG), or at least 100 psig (about 690 kPaG), or at least 200 psig (about 1.38 MPaG), or Range from 0.10 psig (about 690 PaG) to 300 psig (about 2.07 MPaG), or 0.25 psig (about 1.7 kPaG) to 275 psig (about 1.9 MPaG), or 0.50 psig (about 3.4 kPaG) to A range of 250 psig (about 1.72 MPaG), or a range of 1.0 psig (about 6.9 kPaG) to 225 psig (about 1.55 MPaG), or a range of 5.0 psig (about 34 kPaG) to 200 psig (about 1.38 MPaG). Alternatively, it is in the range of 10 psig (about 69 kPaG) to 175 psig (about 1.2 MPaG), or in the range of 25 psig (about 172 kPaG) to 150 psig (about 1.03 MPaG), or in the range of 50 psig (about 345 kPaG) to 100 psig (about 690 kPaG). Here, psig expresses the gauge pressure in psi (pounds per square inch).

As the pressure of the coating liquid in the pressure coating chamber increases, the meniscus pressure increases. Therefore, higher drawing speeds are achieved by stabilizing the meniscus of the coating liquid with high pressure. The pressure of the meniscus of the coating solution provided by the method is greater than 0 psig (0 kPaG), or at least 0.10 psig (about 690 PaG), or at least 0.50 psig (about 3.4 kPaG), or at least 1.0 psig (about 1.0 kPaG). 6.9 kPaG), or at least 5.0 psig (about 34 kPaG), or at least 10 psig (about 69 kPaG), or at least 25 psig (about 172 kPaG), or at least 50 psig (about 345 kPaG), or at least 100 psig (about 690 kPaG), or at least 200 psig. (Approximately 1.38 MPaG), or 0.1 psig (approximately 690 PaG) to 500 psig (approximately 3.4 MPaG), or 1.0 psig (approximately 6.9 kPaG) to 400 psig (approximately 2.76 MPaG), or 5. The range is 0 psig (about 34 kPaG) to 300 psig (about 2.07 MPaG), or 10 psig (about 69 kPaG) to 200 psig (about 1.38 MPaG).

Measures to increase the meniscus pressure are complicated by the effects that occur near the sizing die as the optical fiber exits the coating chamber. As described above, when the wet fiber moves from the guide die to the sizing die, a meniscus of the coating liquid is formed on the fiber and a boundary layer of the coating liquid is formed at the tip of the meniscus. The boundary layer spreads with the fibers as it passes through the coating solution. FIG. 1 shows a calculated (finite element) boundary layer of coating liquid on an optical fiber as the optical fiber passes through the coating chamber. The optical fiber 10 enters the coating chamber 20 through the guide die outlet 30, passes through the coating chamber 20 to reach the sizing die 40, and exits through the sizing die outlet 50. The coating chamber 20 contains a coating liquid, and the optical fiber 10 is wetted with the coating liquid when it enters the coating chamber 20 through the guide die outlet 30. For calculation, wetting of the optical fiber 10 involves the complete movement of the gas boundary layer associated with the optical fiber 10 of the guide die by the coating liquid and occurs without the formation of air bubbles in the coating chamber 20.

When the optical fiber 10 passes through the coating chamber 20, the boundary layer 60 of the coating liquid is formed. The thickness of the boundary layer 60 increases as the optical fiber 10 advances toward the sizing die 40. In the first-order approximation, the thickness of the boundary layer is proportional to (νX / V _f ), where ν is the kinematic viscosity of the coating solution and Χ is the boundary layer with respect to the start of the boundary layer at the tip of the meniscus near the exit of the guide die. It is the distance along the fiber path of the position within, and V _f is the drawing speed of the fiber.

The sizing die 40 includes a tapered surface 70 that shrinks the space available for the coating liquid. When shrinkage occurs, a portion 80 of the coating fluid from the boundary layer 60 is returned from the sizing die 40 to the coating chamber 20. The discharged coating fluid forms a vortex in the coating chamber 20 adjacent to the sizing die 40. The eddy current is a loop-like local flow pattern of the coating liquid having a nearly closed streamline. When the coating liquid recirculates in the vortex during the drawing process, the shear stress associated with the flow raises the temperature of the coating liquid in the vortex.

The shape of the vortex and the temperature distribution within the vortex depend on the design of the sizing die. For example, the size and intensity of the vortex depends on the degree of shrinkage of the space available for the coating solution. Thin fiber coatings require narrower sized dies and cause greater shrinkage. If the shrinkage is greater, a large amount of coating liquid will be expelled from the boundary layer as the fiber enters the taper portion of the sizing die, forming a more pronounced vortex.

The shape of the sizing die also affects the position, shape and temperature distribution of the eddy current. FIG. 2 shows a conventional design of a sizing die. Conventional designs include bells, tapers and lands. FIG. 3 shows the design of the sizing die cone only. The cone-only design does not have a bell part, but includes a cone part and a land part. Further information regarding the design of cones only can be found in US Patent Application Publication No. 20150147467, the disclosure of which is incorporated herein by reference.

FIG. 4 shows the calculated shape and temperature profile of the eddy current formed adjacent to the sizing die having the conventional design shown in FIG. The optical fiber 110 enters the coating chamber portion 120 through the guide die outlet 130 and passes through the outlet 150 of the conventional sizing die 140. The drawing speed of the optical fiber 110 is 50 m / s. A vortex with an outer boundary 160 is formed around the optical fiber 110. Shading in the vortex indicates the temperature profile that occurs in the vortex in steady state. The darker shades correspond to the higher temperatures of the coating liquid present in the vortex. The temperature scale shown on the left shows the temperature in degrees Celsius. The temperature of the coating liquid is highest near the optical fiber 110 and decreases as the distance from the optical fiber 110 increases. The vortex is surrounded by the coating liquid. The vortex boundary 160 corresponds to the position where equalization occurs between the temperature of the coating liquid in the vortex and the temperature of the surrounding coating liquid. For the calculation, the temperature of the coating liquid surrounding the vortex was set to 60 ° C. FIG. 4 shows that the vortex formed by the conventional die extends along the process path of the fiber and the spatial extent of the vortex is limited to the region close to the fiber. FIG. 4 also shows that the maximum temperature in the vortex is about 100 ° C. higher than the temperature of the coating fluid away from the vortex.

FIG. 5 shows the calculated shape and temperature profile of the eddy current formed adjacent to the sizing die with the cone-only design shown in FIG. The optical fiber 210 enters the coating chamber portion 220 through the guide die outlet 230 and passes through the outlet 250 of the cone-only sizing die 240. A vortex with an outer boundary 260 is formed around the optical fiber 210. Shading in the vortex indicates the temperature profile that occurs in the vortex in steady state. The temperature scale shown on the left shows the temperature in degrees Celsius. The darker shades correspond to the higher temperatures of the coating liquid present in the vortex. The temperature of the coating liquid is generally higher near the fiber optic 210 and decreases as it moves away from the fiber optic 210 until equivalence with the temperature of the surrounding coating liquid occurs at the outer boundary 260 of the vortex. For the calculation, the temperature of the coating liquid surrounding the vortex was set to 60 ° C. FIG. 5 shows that the eddy current formed by the cone-only die extends in a direction across the fiber process path. Compared to traditional dies, the vortex formed by cone-only dies is not so closely limited to the space close to the fiber. The vortex extends laterally over a considerable distance away from the process path. FIG. 5 also shows that the maximum temperature in the vortex is about 80 ° C. higher than the temperature of the coating fluid away from the vortex. The heating range of the coating liquid in the vortex is smaller in the cone-only sizing die than in the conventional sizing die shown in FIG.

The heating of the coating liquid generated in the vortex is detrimental to the stability of the meniscus and leads to flooding of the guide die. Flooding is a process defect in which the coating liquid is pushed into the guide die from the guide die outlet by the pressure of the coating liquid in the coating chamber. Flooding usually leads to fiber breakage, which requires the process to shut down. When the coating liquid is heated in a vortex, its viscosity decreases, and the presence of the vortex tends to cause flooding. The heating range and the decrease in viscosity become more pronounced as the drawing speed increases. This is because the higher the drawing speed, the higher the circulating flow rate in the vortex, the greater the shearing effect due to the dissipation of the viscosity, and the higher the heating. For the typical drawing speed in the current manufacturing process, the temperature rise associated with the eddy current (above about 70 ° C.) is sufficient to reduce the viscosity of the coating by an order of magnitude or more. When the drawing speed exceeds the current value, the heating and heat effects associated with the eddy current become more pronounced.

Due to the heating of the coating liquid and the decrease in viscosity, (1) the buoyancy of the coating liquid is increased compared to the surrounding coating liquid, and (2) the pressure required to cause the backflow of the coating liquid to the guide die is reduced. The possibility of flooding increases. As a result, warmer, less viscous coatings that leak out of the vortex and enter the surrounding coatings tend to flow upwards into the coating chamber into the guide die. When the warmer, less viscous coating reaches the meniscus, the meniscus becomes unstable and the fibers dewet. When the fiber dewetting occurs, the drag associated with the liquid boundary layer required to resist the backflow of the coating liquid into the guide die is lost and the pressure required to push the coating liquid into the guide die through the guide die outlet. Decreases. Accordingly, flooding occurs as a result.

Bubbles in the coating liquid also promote flooding. The presence of air bubbles leads to random and chaotic movement of the coating fluid in and around the vortex. Random and chaotic movement promotes leakage of the warmer viscous coating from the vortex and facilitates the movement of the warmer viscous coating towards the meniscus.

To maintain a stable meniscus and continuous, continuous wetting of the fibers, it is necessary to limit the effect of eddy currents on the coating process. The method reduces the harmful effects of eddy currents by supplying a transverse flow of coating liquid to the space between the outlet of the guide die and the inlet of the sizing die. Transverse flow refers to the flow of coating fluid across the fiber process path as the fiber passes through the coating chamber. Lateral refers to any direction that is not parallel to the fiber process path. The transverse flow of the coating liquid mixes or interacts with the coating fluid in the vortex. In one embodiment, the transverse flow of the coating liquid enters the vortex, mixes with the coating liquid in the vortex, flows across the vortex, exits the vortex, and removes or moves a portion of the coating liquid from the vortex. In another embodiment, the lateral flow of the coating liquid is guided around the vortex without entering the vortex. In one embodiment, establishing a transverse flow involves adding a coating solution from an external source to an existing coating solution in the coating chamber and removing the coating solution from the coating chamber. The removed coating liquid is a coating liquid originally present in the coating chamber, a coating liquid added to the coating chamber, or a combination thereof. In one embodiment, a transverse flow of coating liquid is supplied to the pressure coating chamber.

Lateral flow of coating liquid reduces the effects of eddy currents in several ways. First, the temperature of the coating liquid in the transverse flow at the inlet to the coating chamber can be controlled and maintained below the maximum, average or minimum temperature of the coating liquid contained in the vortex. The vortex cools as the cooler coating in the transverse flow interacts with the hotter coating in the vortex. When the vortex cools, the buoyancy of the coating liquid in the vortex decreases and the viscosity increases. This reduces the possibility of the coating liquid leaking from the vortex. In the range where the coating liquid leaks from the vortex, the temperature drops due to the decrease in buoyancy, and the higher the viscosity, the less likely the coating liquid from the vortex reaches the meniscus. When the coating liquid from the vortex reaches the meniscus, the lower temperature and higher viscosity mean that higher pressure is required to push the coating liquid into the guide die. Accordingly, the possibility of flooding is reduced. By maintaining a continuous lateral flow of the coating liquid and continuously removing the coating liquid, the temperature of the coating liquid in the vortex can be controlled.

Second, the cooling of the coating fluid provided by the transverse flow also reduces the temperature gradient within the vortex and the difference in average temperature between the vortex and the surrounding coating fluid. Greater temperature equalization results in a more homogeneous coating with more stable and consistent properties (eg, eddy current pattern, density, viscosity). The improved homogeneity improves the uniformity and concentricity of the coating.

Third, the movement and removal of the coating liquid in the coating chamber reduces the concentration of air bubbles in the coating chamber, whether in or around the vortex. The lateral flow coating fluid is not exposed to the accompanying gas in the coating chamber and enters the coating chamber, which is virtually bubble-free. Therefore, the transverse flow of the coating fluid dilutes the concentration of air bubbles in the coating chamber. When the coating fluid of the coating liquid containing bubbles is removed from the coating chamber, the bubble concentration decreases. Low bubble concentrations minimize the possibility of dewetting and flooding. Low bubble concentrations also eliminate random and chaotic movements within the vortex, which provides a more consistent and stable flow pattern within the vortex and reduces the tendency for coating fluid to leak from the vortex. Improves sex.

Fourth, replenishment of the coating liquid to the coating chamber reduces the concentration of dissolved gas in the coating fluid. As mentioned above, the gas can enter the coating chamber by being accompanied by the fiber as it exits the guide die. Accompaniment can lead to wetting and is not desirable. However, gas can enter the coating chamber even if the fibers are properly wet. Wetting of the fiber involves the formation of a meniscus of the coating on the fiber as it enters the coating. When the meniscus is formed, the gas boundary layer on the fiber is moved. However, the meniscus is exposed to gas from the displaced boundary layer. Common process gases (eg, air, CO ₂ , He) present in the guide die are soluble in the coating fluid commonly used to coat fibers. As the drawing process operates over time, the concentration of gas dissolved in the coating liquid increases and eventually reaches saturation levels.

When the coating liquid is saturated with gas, two adverse effects occur. First, the dissolution of gas in the coating liquid is one of the steps associated with the wetting process. The rate of wetting is related to the permeability of the gas from the gas boundary layer of the fiber to the coating solution (see, eg, Jacqmin, D .; Journal of Fluid Technologies, 455, 347-358 (2002)). Gas permeability is proportional to the solubility and diffusion rate of the gas in the coating solution. If the coating liquid is saturated with gas, no further gas can be dissolved in the coating liquid and the gas from the gas boundary layer of the fiber cannot enter the coating liquid. As a result, dewetting can occur. Secondly, since the gas cannot be dissolved in the coating liquid, there is a high possibility that bubbles are formed in the coating liquid. When the gas dissolves in the coating liquid, the gas that may form bubbles in the coating liquid is removed. Dissolution suppresses the formation of bubbles. However, when the coating liquid is saturated with gas, dissolution is no longer possible and it becomes more common for the coating liquid to be contaminated with gas in the form of bubbles. Replenishing the saturated coating with a new coating avoids saturation and maintains consistent dissolution of the gas in the coating, thus facilitating wetting and suppressing the formation of air bubbles.

Fifth, lowering the temperature of the coating liquid in the coating chamber increases the solubility of common process gases in the coating liquid. The higher the solubility, the greater the dissolution of the gas in the coating solution and the longer it takes for saturation to occur. This allows for longer operating times before concerns about dewetting and air bubble confinement associated with coating liquid saturation arise.

Establishing a lateral flow of coating liquid involves guiding the flow of coating liquid into the space between the outlet of the guide die and the inlet of the sizing die. This space defines a channel through which the coating liquid flows laterally. The process path coincides with the optical fiber and extends from the exit of the guide die to the entrance of the sizing die. The transverse flow crosses , passes through , and / or rotates across the process path to mix, dilute, or (thermally or mechanically) interact with the coating solution present in the coating chamber. The lateral flow rate is adjusted to counter the harmful effects of eddy currents. As the drawing speed increases, it is preferable to increase the lateral flow rate. In various embodiments, the lateral flow rate is greater than 0.1 cm ³ / s, or greater than 0.2 cm ³ / s, or greater than 0.3 cm ³ / s, or greater than 0.4 cm ³ / s. Or more than 0.5 cm ³ / s, or more than 0.75 cm ³ / s, or more than 1.0 cm ³ / s, or more than 2.5 cm ³ / s, or more than 5.0 cm ³ / s, Or the range of 0.1 cm ³ / s to 20 cm ³ / s, or the range of 0.1 cm ³ / s to 10 cm ³ / s, or the range of 0.1 cm ³ / s to 5.0 cm ³ / s, or 0. 2 cm ³ / s to 20 cm ³ / s range, or 0.2 cm ³ / s to 10 cm ³ / s range, or 0.2 cm ³ / s to 5.0 cm ³ / s range, or 0.5 cm ³ / The range is s to 20 cm ³ / s, or 0.5 cm ³ / s to 10 cm ³ / s, or 0.5 cm ³ / s to 5.0 cm ³ / s.

FIG. 6 shows a modification of the configuration shown in FIG. 4, including a transverse flow of coating liquid in the channel between the guide die outlet 130 and the sizing die 140. The transverse flow includes the introduction of the coating liquid 170 and the vortex and / or the removal of the coating liquid from the coating chamber 180. Similarly, FIG. 7 shows a modification of the configuration shown in FIG. 5, including a transverse flow of coating liquid in the channel between the guide die outlet 230 and the sizing die 240. The transverse flow includes the introduction of the coating liquid 270 and the eddy current and / or the removal of the coating liquid from the coating chamber 280. In one embodiment, the lateral flow rate corresponds to the amount of coating liquid introduced at the inlet to the coating chamber. In another embodiment, the lateral flow rate corresponds to the rate of removal of the coating liquid from the coating chamber. In a further embodiment, the lateral flow rate is measured by placing a sensor or flow meter in the coating chamber near the vortex.

In various embodiments, the introduction amount of the coating liquid used to generate the transverse flow is greater than 0.1 cm ³ / s, or greater than 0.2 cm ³ / s, or 0.3 cm ³ / s. More than, or more than 0.4 cm ³ / s, more than 0.5 cm ³ / s, more than 0.75 cm ^{3 / s, more than 1.0 cm 3 /} s, or more than 2.5 cm ³ / s More than, or more than 5.0 cm ³ / s, or in the range of 0.1 cm ³ / s to 20 cm ³ / s, or in the range of 0.1 cm ³ / s to 10 cm ³ / s, or 0.1 cm ³ / s. Range of up to 5.0 cm ³ / s, or 0.2 cm ³ / s to 20 cm ³ / s, or 0.2 cm ³ / s to 10 cm ³ / s, or 0.2 cm ³ / s to 5. Range of 0 cm ³ / s, or range of 0.5 cm ³ / s to 20 cm ³ / s, or range of 0.5 cm ³ / s to 10 cm ³ / s, or range of 0.5 cm ^{3 / s to 5.0 cm 3 /} It is in the range of s.

In various embodiments, the amount of coating liquid removed from the coating chamber is greater than 0.1 cm ³ / s, or greater than 0.2 cm ³ / s, or greater than 0.3 cm ³ / s, or 0.4 cm. More than ³ / s, or more than 0.5 cm ³ / s, or more than 0.75 cm ³ / s, or more than 1.0 cm ³ / s, or more than 2.5 cm ³ / s, or 5.0 cm More than ³ / s, or 0.1 cm ³ / s to 20 cm ³ / s, or 0.1 cm ³ / s to 10 cm ³ / s, or 0.1 cm ³ / s to 5.0 cm ³ / s Range, or 0.2 cm ³ / s to 20 cm ³ / s, or 0.2 cm ³ / s to 10 cm ³ / s, or 0.2 cm ^{3 / s to 5.0 cm 3 /} s, Or the range of 0.5 cm ³ / s to 20 cm ³ / s, or the range of 0.5 cm ³ / s to 10 cm ³ / s, or the range of 0.5 cm ³ / s to 5.0 cm ³ / s.

In order to accommodate the lateral flow of the coating liquid in one embodiment, the coating chamber shall include an inlet for delivering the lateral flow of the coating liquid and an outlet for removing the lateral flow of the coating liquid. Is adapted to. The inlet and outlet are different from the fiber inlet and outlet points into the coating chamber. FIG. 8 shows an embodiment of a coating chamber including an inlet for supplying the coating liquid from an external source to the coating chamber and an outlet for removing the coating liquid from the coating chamber. The flow of the coating liquid is shown by a gray arrow in FIG. The coating liquid flows from the inlet into the coating chamber and passes through the optical fiber laterally in the channel between the guide die and the sizing die. The lateral flow coating liquid exits the channel and is removed from the coating chamber at the exit. The inlet for supplying the coating liquid from an external source is different from the entry point (guide die exit) of the optical fiber into the coating chamber. The outlet for removing the coating liquid from the coating chamber is different from the entry and exit points of the optical fiber from the sizing die. In steady state, the amount of coating liquid removed at the outlet is approximately equal to the amount of coating liquid supplied at the inlet. The sizing die removes the coating liquid in the form of a thin layer on the optical fiber, and if present, the coating liquid leaks to the guide die, resulting in an inaccurate balance of coating liquid volume at the inlet and outlet.

In the embodiments of FIGS. 4 and 5, the vortex occupies a significant portion of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber.

As a result, as shown in FIG. 8, it is preferred that the lateral flow coating liquid interact with most of the vortex to facilitate mitigation of the vortex effect on fiber wetting. In FIG. 8, the fiber inlet to the coating chamber corresponds to the outlet of the guide die and the fiber outlet from the coating chamber corresponds to the inlet to the sizing die. In one embodiment, the interaction of a transverse flow with a vortex is determined by the partial overlap of the cross section of the transverse flow with the vortex. The transverse flow is characterized by a cross section of a plane perpendicular to the direction of the transverse flow. This cross section is a two-dimensional region defined by a perimeter with shape and size. The shape and size of the perimeter is influenced by factors such as the shape and size of the inlet that supplies the lateral flow to the coating chamber and the dimensions of the channel between the guide die and the sizing die through which the lateral flow passes. In various embodiments, the perimeter shape is circular, oval, square, rectangular or irregular. Perimeter size is characterized by cross-sectional dimensions. The cross-sectional dimensions correspond to the longest line segment connecting the two points of perimeter of the cross-section. For example, if the shape of the perimeter is circular, the cross-sectional dimension is the diameter. If the perimeter shape is square or rectangular, the cross-sectional dimension is the diagonal length. When the shape of the perimeter is elliptical, the cross-sectional dimension is the length of the major axis of the ellipse.

To enhance the interaction between the lateral flow of the coating liquid and the eddy current, the cross-sectional dimensions of the lateral flow of the coating liquid exceed 30% of the distance between the outlet of the guide die and the inlet of the sizing die, or guide. More than 40% of the distance between the exit of the die and the entrance of the sizing die, or more than 50% of the distance between the exit of the guide die and the entrance of the sizing die, or the exit of the guide die and the entrance of the sizing die More than 70% of the distance between, or more than 90% of the distance between the exit of the guide die and the entrance of the sizing die, or 30% of the distance between the exit of the guide die and the entrance of the sizing die. In the range of ~ 100%, or in the range of 50% to 100% of the distance between the exit of the guide die and the entrance of the sizing die, or 70% to 100% of the distance between the exit of the guide die and the entrance of the sizing die. %, Or 30% to 90% of the distance between the exit of the guide die and the entrance of the sizing die.

In other embodiments, the cross-sectional dimensions of the lateral flow of coating liquid exceed 30% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet and coating into the coating chamber. More than 40% of the distance between the fiber inlet from the chamber, or more than 50% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet and coating to the coating chamber More than 70% of the distance between the fiber inlet from the chamber, or more than 90% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet and coating to the coating chamber The range of 30% to 100% of the distance between the fiber outlet from the chamber, or the range of 50% to 100% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the coating chamber. 70% to 100% of the distance between the fiber inlet to and the fiber outlet from the coating chamber, or 30% to 90% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber. Is the range of.

In one embodiment, the cross-sectional dimensions of the lateral flow of the coating liquid are controlled by the dimensions of the inlet that supplies the lateral flow of the coating liquid to the coating chamber. The inlet includes an opening at the interface with the coating chamber through which the lateral flow of coating liquid is supplied. The entrance has a cross-sectional area determined by the size and shape of the opening and is characterized by cross-sectional dimensions. The cross-sectional dimension of the entrance corresponds to the longest line segment connecting the two points of the perimeter of the opening.

In different embodiments, the cross-sectional dimensions of the inlet exceed 30% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or with the fiber inlet to the coating chamber and the fiber outlet from the coating chamber. More than 40% of the distance between, or more than 50% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet to the coating chamber and the fiber outlet from the coating chamber More than 70% of the distance between, or more than 90% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet to the coating chamber and the fiber outlet from the coating chamber The range of 30% to 100% of the distance between, or the range of 50% to 100% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber, or the fiber inlet and coating to the coating chamber. The range is 70% to 100% of the distance between the fiber outlet from the chamber, or 30% to 90% of the distance between the fiber inlet to the coating chamber and the fiber outlet from the coating chamber.

In different embodiments, the cross-sectional dimensions of the inlet exceed 30% of the distance between the exit of the guide die and the inlet of the sizing die, or 40% of the distance between the exit of the guide die and the inlet of the sizing die. Exceeds, or exceeds 50% of the distance between the exit of the guide die and the entrance of the sizing die, or exceeds 70% of the distance between the exit of the guide die and the entrance of the sizing die, or with the exit of the guide die More than 90% of the distance between the entrance of the sizing die, or 30% to 100% of the distance between the exit of the guide die and the entrance of the sizing die, or between the exit of the guide die and the entrance of the sizing die 50% to 100% of the distance between, or 70% to 100% of the distance between the exit of the guide die and the entrance of the sizing die, or between the exit of the guide die and the entrance of the sizing die. It is in the range of 30% to 90% of the distance.

The temperature and / or flow rate of the coating liquid supplied at the inlet can be controlled to control the thermal environment of the coating liquid in the coating chamber or vortex. The temperature of the coating liquid supplied at the inlet is below the maximum temperature of the coating liquid in the vortex, or below the average temperature of the coating liquid in the vortex, or below the minimum temperature of the coating liquid in the vortex, or the coating outside the vortex. It is below the average temperature of the coating liquid in the chamber.

Management of the thermal environment of the coating liquid involves minimizing the temperature difference of the coating liquid in the vortex. By including a transverse flow of coating liquid in the channel between the guide die and the sizing die, the difference between the maximum temperature of the coating fluid in the vortex and the minimum temperature of the coating fluid in the vortex is less than 80 ° C or 60 ° C. Below ° C, below 50 ° C, below 40 ° C, or below 30 ° C.

In different embodiments, the temperature of the coating liquid supplied at the inlet of the coating chamber is at least 5 ° C, at least 10 ° C, or at least 20 ° C, or at least 30 ° C lower, or 5 below the average temperature of the coating liquid in the vortex. It is lower by an amount in the range of ° C. to 40 ° C. or by an amount in the range of 10 ° C. to 30 ° C.

Management of the thermal environment of the coating liquid involves minimizing the difference between the temperature of the coating liquid in the vortex and the temperature of the coating liquid surrounding the vortex. By including a transverse flow of coating in the channel between the guide die and the sizing die, the temperature difference between the maximum temperature of the coating in the vortex and the coating surrounding the vortex is less than 80 ° C or 60 ° C. Less than, less than 50 ° C, less than 40 ° C, or less than 30 ° C.

Coating assemblies characterized by a transverse flow of coating fluid according to the specification are utilized for the application of one or more coatings to an optical fiber. Typical optical fibers include a low modulus primary coating on glass fiber and a high modulus secondary coating on the primary coating. In many cases, a colored layer is also formed on the secondary coating. The advantages associated with the transverse flow of the coating liquid extend to any of the coatings formed on the optical fiber. When applying multiple coatings to a fiber, the liquid primary coating composition is applied to the fiber at a location along the process path upstream of where the liquid secondary coating composition is applied to the fiber. In one embodiment, the liquid primary coating composition is cured prior to applying the liquid secondary coating composition (wet-on-dry process). In another embodiment, the liquid primary coating composition is uncured prior to applying the liquid secondary coating composition (wet-on-wet process). When applied, the liquid colored layer composition is applied at a location along the process path downstream from the application site of the liquid secondary coating composition. In one embodiment, the liquid secondary coating composition is cured prior to applying the liquid colored layer composition (wet-on-dry process). In another embodiment, the liquid secondary coating composition is uncured prior to applying the liquid colored layer composition (wet-on-wet process).

FIG. 9 shows an embodiment in which the primary and secondary coating liquids are applied to an optical fiber in a wet-on-wet process. Using the coating unit 300, the liquid primary coating composition is applied to the optical fiber 305. The optical fiber 305 is drawn in the direction indicated by the particular drawing speed. The optical fiber 305 is drawn through the guide die 310 to the coating chamber 315, through the coating chamber 315 to the sizing die 320, and through the sizing die 320 to the downstream coating unit 325. The primary coating liquid is applied to the optical fiber 305 in the coating chamber 315. The primary coating liquid is supplied to the coating chamber 315 at the inlet 330 and removed from the coating chamber 315 at the outlet 335. The primary coating liquid flows laterally 340 and 345 within the coating chamber 315. The optical fiber 305 enters the coating unit 325 with the guide die 350, is drawn to the coating chamber 355 through the guide die 350, is drawn to the sizing die 360 through the coating chamber 355, and is drawn to the downstream processing unit (not shown) through the sizing die 360. It is drawn. The secondary coating liquid is applied to the optical fiber 305 in the coating chamber 355. The secondary coating liquid is supplied to the coating chamber 355 at the inlet 365 and removed from the coating chamber 355 at the outlet 370. The secondary coating liquid flows laterally 375 and 380 within the coating chamber 355. The lateral flow of the coating liquid is depicted to occur in the same or similar lateral directions within the coating chambers 315 and 355, while the lateral flow of the coating liquid occurs in different directions in the coating chambers 315 and 355. It is understood to get.

FIG. 10 shows another embodiment in which the primary and secondary coating liquids are applied to an optical fiber in a wet-on-wet process. Using the coating unit 400, liquid primary and secondary coating compositions are applied to the optical fiber 405. The optical fiber 405 is drawn in the direction indicated by the specific drawing speed. The optical fiber 405 is drawn to the coating chamber 415 through the guide die 410, to the hybrid die 420 through the coating chamber 415, to the coating chamber 425 through the hybrid die 420, to the sizing die 430 through the coating chamber 425, and to the sizing die. It is drawn through 430 to the downstream process unit (not shown). The hybrid die 420 acts as a sizing die for the optical fiber 405 when exiting the coating chamber 415 and as a guide die for the optical fiber 405 when entering the coating chamber 425. The primary coating liquid is applied to the optical fiber 405 in the coating chamber 415. The primary coating liquid is supplied to the coating chamber 415 at the inlet 435 and removed from the coating chamber 415 at the outlet 440. The primary coating liquid flows laterally 445 and 450 within the coating chamber 415. Optical fiber 405 enters the coating chamber 425 through a hybrid die at 420. The secondary coating liquid is applied to the optical fiber 405 in the coating chamber 425. The secondary coating liquid is supplied to the coating chamber 425 at the inlet 455 and removed from the coating chamber 425 at the outlet 460. The secondary coating liquid flows laterally 465 and 470 within the coating chamber 425. The lateral flow of the coating liquid is depicted to occur in the same or similar lateral directions within the coating chambers 415 and 425, while the lateral flow of the coating liquid occurs in different directions in the coating chambers 415 and 425. It is understood to get.

In another embodiment, the coating liquid removed from the coating chamber is recycled into the coating chamber. The coating liquid removed from the coating chamber is sent to a return loop that delivers the removed coating liquid directly to the coating chamber, or to an external source of coating liquid operably linked to the inlet of the coating chamber.

In a preferred embodiment, the guide die does not contain a coating solution. In another preferred embodiment, guide die flooding does not occur. In a more preferred embodiment, the coating liquid associated with the transverse flow does not enter the guide die.

The preferred coating liquid is a curable coating liquid. The curable coating liquid contains one or more curable components. As used herein, the term "curable" binds (bonds) a component to itself or other components forming a polymeric coating material when the component is exposed to a suitable curing energy source. It is meant to include one or more curable functional groups capable of forming a covalent bond involved in it. The cure product obtained by curing the curable coating solution is a coating. The curing process is triggered by one of several forms of energy. The form of energy includes radiant energy or thermal energy. A radiation curable component is a component that is induced to undergo a curing reaction when exposed to radiation of appropriate intensity and wavelength for a sufficient period of time. The radiation curing reaction preferably occurs in the presence of a photoinitiator. The radiation curable component is also thermosetting in some cases. Similarly, a thermosetting component is a component that is induced to undergo a curing reaction when exposed to sufficient intensity of heat energy for a sufficient period of time. The thermosetting component is also radiation curable in some cases. Curable components include monomers, oligomers and polymers.

The curable component comprises one or more curable functional groups. The curable component having only one curable functional group is a monofunctional curable component. The curable component having two or more curable functional groups is a polyfunctional curable component. The polyfunctional curable component contains two or more functional groups capable of forming covalent bonds during the curing process and can introduce crosslinks into the polymer network formed during the curing process. The polyfunctional curable component is also referred to as a "crosslinking agent" or "curable crosslinking agent". Examples of functional groups involved in covalent bond formation during the curing process are shown below.

The coating composition comprises a single monomer or a combination of monomers. Monomers include ethylenically unsaturated compounds, ethoxylated acrylates, ethoxylated alkylphenol monoacrylates, propylene oxide acrylates, n-propylene oxide acrylates, isopropylene oxide acrylates, monofunctional acrylates, monofunctional aliphatic epoxy acrylates, and polyfunctionals. Includes sex acrylates, polyfunctional aliphatic epoxy acrylates and combinations thereof.

In one embodiment, the monomer component of the curable coating liquid comprises an ethylenically unsaturated monomer. The monomer contains a polymerizable group and / or a functional group which is a group that promotes or enables cross-linking. The monomer is a monofunctional monomer or a polyfunctional monomer. In the combination of two or more monomers, the constituent monomer is a monofunctional monomer, a polyfunctional monomer, or a combination of a monofunctional monomer and a polyfunctional monomer. Suitable functional groups for ethylenically unsaturated monomers include, but are not limited to, (meth) acrylates, acrylamides, N-vinylamides, styrenes, vinyl ethers, vinyl esters, acid esters and combinations thereof.

Exemplary monofunctional ethylenically unsaturated monomers for curable coatings include hydroxyalkyl acrylates such as 2-hydroxyethyl acrylates, 2-hydroxypropyl acrylates and 2-hydroxybutyl acrylates; long and short chain alkyls. Acrylate such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, amyl acrylate, isobutyl acrylate, t-butyl acrylate, pentyl acrylate, isoamyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate, isooctyl acrylate, 2- Ethylhexyl acrylate, nonyl acrylate, decyl acrylate, isodecyl acrylate, undecyl acrylate, dodecyl acrylate, lauryl acrylate, octadecyl acrylate and stearyl acrylate; aminoalkyl acrylates such as dimethylaminoethyl acrylate, diethylaminoethyl acrylate and 7-amino-3,7 -Dimethyloctyl acrylates; alkoxyalkyl acrylates such as butoxyethyl acrylates, phenoxyethyl acrylates (eg SR339, Sartomer Company, Inc.) and ethoxyethoxyethyl acrylates; monocyclic and polycyclic cyclic aromatic or non-aromatic acrylates such as. Cyclohexyl acrylate, benzyl acrylate, dicyclopentadiene acrylate, dicyclopentanyl acrylate, tricyclodecanyl acrylate, bornyl acrylate, isobornyl acrylate (eg SR423, Sartomer Company, Inc.), tetrahydrofurfuryl acrylate (eg, eg. SR285, Sartomer Company, Inc.), caprolactone acrylates (eg SR495, Sartomer Company, Inc.) and acryloylmorpholin; alcohol-based acrylates such as polyethylene glycol monoacrylates, polypropylene glycol monoacrylates, methoxyethylene glycol acrylates, methoxypolypropylene glycols. Acrylate, methoxypolyethylene glycol acrylate, ethoxydiethylene glycol acrylate, And various alkoxylated alkylphenol acrylates such as ethoxylated (4) nonylphenol acrylates (eg Photomer® 4066, IGM Resins); acrylamides such as diacetoneacrylamide, isobutoxymethylacrylamide, N, N'-dimethylaminopropyl. Includes acrylamide, N, N-dimethylacrylamide, N, N-diacetone and t-octylacrylamide; vinyl compounds such as N-vinylpyrrolidone and N-vinylcaprolactam; and acid esters such as maleic acid and fumaric acid esters. However, it is not limited to these. Regarding the above-mentioned long-chain and short-chain acrylate alkyls, the short-chain alkyl acrylate is an alkyl group having 6 or less carbon atoms, and the long-chain alkyl acrylate is an alkyl group having 7 or more carbon atoms.

Typical radiation curable ethylenically unsaturated monomers include alkoxylated monomers having one or more acrylate or methacrylate groups. The alkoxylated monomer contains one or more alkoxylene groups, wherein the type of alkoxylene group is —OR—, where R is a linear or branched hydrocarbon. Examples of alkoxylene groups include ethoxylen (-O-CH ₂ -CH _2- ), n-propoxylen (-O-CH ₂ -CH ₂ -CH _2- ), and isopropoxylen (-O-CH _2- ). CH (CH ₃ )-) and the like are included. As used herein, the degree of alkoxylation refers to the number of alkoxylene groups in the monomer. In one embodiment, the alkoxylen group is continuously attached in the monomer.

Typical polyfunctional ethylenically unsaturated monomers for curable coatings include, but are limited to, alkoxylated bisphenol A diacrylates, such as ethoxylated bisphenol A diacrylates having a degree of alkoxylation of 2 or greater. Not done. Monomer components of the secondary composition include SR349 and SR601, available from ethoxylated bisphenol A diacrylates (eg, Sartomer Company, Inc. (Westchester, Pennsylvania)) having a degree of ethoxylation ranging from 2 to about 30. Also, Photomer 4025 and Photomer 4028) available from IGM Resins, or propoxylated bisphenol A diacrylates having a degree of propoxylation of 2 or more, eg, 2 to about 30; trimethylolpropane polyacrylate with and without alkoxylation. For example, ethoxylated trimethylolpropane triacrylates having an ethoxylated degree of 3 or more, for example, in the range of 3 to about 30 (for example, Photomer 4149, IGM Resins, and SR499, Sartomer Company, Inc.); For example, propoxylated trimethylolpropane triacrylate in the range of 3 to 30 (eg, Photomer 4072, IGM Resins and SR492, Sartomer); ditrimethylolpropane tetraacrylate (eg, Photomer 4355, IGM Resins); alkoxylated glyceryl triacrylate. For example, propoxylated glyceryl triacrylates having a degree of propoxylation of 3 or more (eg, Photomer 4096, IGM Resins and SR9020, Sartomer); erythritol polyacrylates with and without alkoxylation, such as pentaerythritol tetraacrylate (eg, Sartomer). SR295 available from Company, Inc. (Westchester, Pennsylvania), ethoxylated pentaerythritol tetraacrylates (eg SR494, Sartomer Company, Inc.) and dipentaerythritol pentaacrylates (eg, Photomer 4399, IGM Resins, and). SR399, Sartomer Company, Inc.); Isocyanurate polyacrylates formed by the reaction of appropriate functional isocyanurates with acrylic acid or acryloyl chloride, such as tris- (2-hydroxyethyl) isocyanurate triacrylate. (For example, SR368, Sartomer Company, Inc. ) And tris- (2-hydroxyethyl) isocyanurate diacrylate; alcohol polyacrylates with and without alkoxylation, such as tricyclodecanedimethanol diacrylate (eg, CD406, Sartomer Company, Inc.) and degree of ethoxylation. Two or more, eg, ethoxylated polyethylene glycol diacrylates in the range of about 2-30; epoxy acrylates formed by adding acrylates to bisphenol A diglycidyl ethers and the like (eg, MeOH 3016, IGM Resins); and monocycles and Polycyclic cyclic aromatic or non-aromatic polyacrylates, such as dicyclopentadiene diacrylates and dicyclopentane diacrylates, may be included.

In the embodiment, the monomer component of the coating liquid contains the general formula R ₂ -R ₁ -O- (CH ₂ CH ₃ CH-O) _q -COCH = CH ₂ [in the formula, R ₁ and R ₂ are aliphatic. , Aromatic or a mixture of both, q = 1-10], or R1 _- O- (CH ₂ CH ₃ CH-O) _q -COCH = CH ₂ [in the formula, R ₁ is , Aliphatic or aromatic, q = 1-10]. Representative examples include ethylenically unsaturated monomers such as lauryl acrylates (eg SR335 available from Sartomer Company, Inc., AGEFLEX® FA12 available from BASF, PHOTOMER 4812 available from IGM Resins). Nonyl ethoxylated phenol acrylates (eg, SR504 available from Sartomer Company, Inc. and PHOTOMER 4066 available from IGM Resins), caprolactone acrylates (eg, SR495 and Dow Chemical available from Sartomer Company, Inc.). TONE ™ M-100), phenoxyethyl acrylates (eg, SR339 available from Sartomer Company, Inc., AGEFLEX PEA available from BASF and PHOTOMER 4035 available from IGM Resins), isooctyl acrylates (eg, eg). SR440 available from Saturmer Company, Inc. and AGEFLEX FA8 available from BASF), tridecyl acrylates (eg SR489 available from Saturmer Company, Inc.), isobornyl acrylates (eg, Sartomer Company, Inc.). Available from SR506 and CPS Chemical Co. available from AGEFLEX IBOA), tetrahydrofurfuryl acrylates (eg, SR285 available from Saturmer Company, Inc.), stearyl acrylates (eg, available from Saturmer Company, Inc.). SR257), isodecyl acrylate (eg, SR395 available from Saturmer Company, Inc. and AGEFLEX FA10 available from BASF), 2- (2-ethoxyethoxy) ethyl acrylate (eg, obtained from Saturmer Company, Inc.). Possible SR256), epoxy acrylates (eg, CN120 available from the Saltomer Company and EBECRYL® 3201 and 3604 available from Cytec Industries Inc.), lauryl oxyglycy Includes are zill acrylates (eg, CN130 available from the Sartomer Company) and phenoxyglycidyl acrylates (eg, CN131 available from the Sartomer Company) and combinations thereof.

In some embodiments, the monomer component of the coating solution comprises a polyfunctional (meth) acrylate. As used herein, the term "(meth) acrylate" means acrylate or methacrylate. A polyfunctional (meth) acrylate is a (meth) acrylate having two or more polymerizable (meth) acrylate moieties per molecule or three or more polymerizable (meth) acrylate moieties per molecule. Examples of polyfunctional (meth) acrylates include dipentaerythritol monohydroxypentaacrylates (eg PHOTOMER 4399 available from IGM Resins); trimethylolpropane polyacrylates with and without alkoxylation, such as trimethylolpropane triacrylates. , Ditrimethylolpropane tetraacrylates (eg, PHOTOMER 4355, IGM Resins); alkoxylated glyceryl triacrylates, eg, propoxylated glyceryl triacrylates with 3 or more propoxylation (eg: PHOTOMER 4096, IGM Resins); and alkoxylation. With and without erythritol polyacrylates, such as pentaerythritol tetraacrylate (eg SR295 available from Sartomer Company, Inc. (Westchester, Pennsylvania)), ethoxylated pentaerythritol tetraacrylate (eg SR494, Sartomer Company, Inc.). ), Dipentaerythritol pentaacrylate (eg, PHOTOMER 4399, IGM Resins and SR399, Sartomer Company, Inc.), Tripropylene glycol di (meth) acrylate, propoxylated hexanediol di (meth) acrylate, tetrapropylene glycol di (eg). Includes meth) acrylates and pentapropylene glycol di (meth) acrylates.

In one embodiment, the monomer component of the coating solution comprises N-vinylamide, such as N-vinyllactam, or N-vinylpyrrolidinone, or N-vinylcaprolactam.

The curable coating liquid optionally contains one or more oligomers. One class of any oligomer is an ethylenically unsaturated oligomer. Suitable optional oligomers include monofunctional oligomers, polyfunctional oligomers, or combinations of monofunctional oligomers with polyfunctional oligomers. In some embodiments, any oligomer may include aliphatic and aromatic urethane (meth) acrylate oligomers, urea (meth) acrylate oligomers, polyester and polyether (meth) acrylate oligomers, acrylicized acrylic oligomers, polybutadiene (meth). ) Acrylate oligomers, polycarbonate (meth) acrylate oligomers, and melamine (meth) acrylate oligomers or combinations thereof. The curable coating liquid may not contain a urethane group, a group that reacts to form a urethane group, a urethane acrylate compound, a urethane oligomer, or a urethane acrylate oligomer.

The polymerization initiator accelerates the initiation of the polymerization process associated with the curing of the coating composition to form the coating. Polymerization initiators include heat initiators, chemical initiators, electron beam initiators and photoinitiators. Photoinitiators include ketone photoinitiators and / or phosphine oxide additives. When used in the photoformation of the coatings of the present disclosure, the photoinitiator is present in sufficient quantity to allow rapid radiation curing. The wavelength of the cured radiation is infrared, visible or ultraviolet.

Typical photoinitiators include 1-hydroxycyclohexylphenylketone (eg, IRGACURE® 184 available from BASF); bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine. Oxides (eg, commercially available blends IRGACURE 1800, 1850 and 1700 available from BASF); 2,2-dimethoxy-2-phenylacetophenone (eg IRGACURE 651 available from BASF); bis (2,4,6- Trimethylbenzoyl) -Phenylphosphinoxide (IRGACURE 819); (2,4,6-trimethylbenzoyl) Diphenylphosphinoxide (available from LUCIRIN® TPO, BASF (Munich, Germany)); ethoxy (2,4) 6-trimethylbenzoyl) -Phenylphosphinoxide (LUCIRIN TPO-L of BASF); (2,4,6-triethylbenzoyl) diphenylphosphinoxide (eg, commercially available blend Darocur® 4265, BASF); 2-hydroxy -2-Methyl-1-phenylpropan-1-one (eg, commercially available blend Darocur 4265, BASF) and combinations thereof are included.

In addition to the monomers, oligomers and / or oligomeric materials, and polymerization initiators, the coating composition optionally comprises one or more additives. Additives include adhesion promoters, strength additives, antioxidants, catalysts, stabilizers, optical brighteners, property-enhancing additives, amine synergists, waxes, lubricants and / or slip agents.

An embodiment of the method comprises curing a coating solution on an optical fiber. In one embodiment, the curable coating liquid is cured with an LED light source or a laser light source. In one embodiment, the LED light source is a UV LED light source. The peak wavelength of the LED or laser light source is less than 410 nm, or less than 405 nm, or less than 400 nm, or less than 395 nm, or in the range of 340 nm to 410 nm, or 350 nm to 405 nm, or 360 nm to 405 nm, or 365 nm. The wavelength is in the range of ~ 400 nm, or 370 nm to 395 nm, or 375 nm to 390 nm, or 375 nm to 400 nm, or 380 nm to 400 nm.

Typical radiation curable ethylenically unsaturated monomers contained an alkoxylated monomer having one or more acrylate or methacrylate groups. The alkoxylated monomer contains one or more alkoxylene groups, wherein the type of alkoxylene group is —OR—, where R is a linear or branched hydrocarbon. Examples of alkoxylene groups include ethoxylen (-O-CH ₂ -CH _2- ), n-propoxylen (-O-CH ₂ -CH ₂ -CH _2- ), and isopropoxylen (-O-CH _2- ). CH (CH ₃ )-) and the like are included. As used herein, the degree of alkoxylation refers to the number of alkoxylene groups in the monomer. In one embodiment, the alkoxylen group is continuously attached in the monomer (see ID 27449 for a description of the secondary coating).

Unless otherwise stated, none of the methods described herein are intended to be construed as requiring the steps to be performed in a particular order. Therefore, if the method claim does not actually state the order in which the steps should be followed, or if the claim or specification does not specifically state that the steps are limited to a particular order, then infer any particular order. Not intended to do.

It will be apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit or scope of the illustrated embodiments. Modifications, combinations, sub-combinations and modifications of disclosed embodiments incorporating the intent and content of the illustrated embodiments may come to mind to those of skill in the art, so the specification is with all within the appended claims. It should be construed to include those equivalents.

Hereinafter, preferred embodiments of the present invention will be described in terms of terms.

Embodiment 1
A method of processing optical fiber, which is as follows:
A step of drawing an optical fiber in a drawing direction along a process path through a coating chamber containing a coating liquid for coating the optical fiber.
A step of guiding a separate flow of coating fluid through the coating chamber in a direction across the drawing direction, wherein the separate flow of coating liquid crosses and passes through the process path in the drawing direction. And / or a method comprising a step of turning and mixing, diluting, or thermally or mechanically interacting with the coating solution contained in the coating chamber.

Embodiment 2
The method according to the first embodiment, wherein the coating chamber is pressurized.

Embodiment 3
The method according to embodiment 1 or 2, wherein the optical fiber enters the coating chamber through a guide die.

Embodiment 4
The method of embodiment 3, wherein the optical fiber is drawn through the coating chamber to a sizing die.

Embodiment 5
4. The method of embodiment 4, wherein a separate stream of the coating solution is guided through a lateral induction channel located within the coating chamber between the guide die and the sizing die.

Embodiment 6
The guide die includes a bell portion, a taper portion and a land portion, or the guide die includes a cone-only die, wherein the cone-only die includes a cone portion and a land portion and a bell portion. The method according to any one of embodiments 3 to 5, which does not include.

Embodiment 7
The optical fiber is drawn at a drawing speed of at least 30 m / s, for example, the drawing speed is at least 40 m / s, preferably the drawing speed is at least 50 m / s, and more preferably the drawing speed is. The method according to any one of embodiments 1 to 6, which is in the range of 40 m / s to 80 m / s.

8th embodiment
Further comprising the step of curing the coating liquid after the optical fiber exits the sizing die, wherein the curing is preferably achieved with an LED light source, any one of embodiments 4-6. the method of.

Embodiment 9
The coating liquid is as follows:
Radiation curable compounds,
The method according to any one of embodiments 1 to 8, comprising one or more of an ethylenically unsaturated compound and an acrylate compound or a methacrylate compound.

Embodiment 10
The coating chamber is described below:
Pressure above 0 psig (0 kPaG),
A pressure of at least 0.10 psig (about 690 PaG),
At least 1.0 psig (about 6.9 kPaG) pressure,
At least 5.0 psig pressure (about 34 kPaG),
At least 10 psig pressure (about 69 kPaG),
Pressure in the range of 0.10 psig (about 690 PaG) to 300 psig (about 2.07 MPaG),
Pressure in the range of 1.0 psig (about 6.9 kPaG) to 225 psig (about 1.55 MPaG),
The method according to any one of embodiments 1 to 9, wherein the pressure is pressurized to a pressure selected from a pressure in the range of 5.0 psig (about 34 kPaG) to 200 psig (about 1.38 MPaG).

Embodiment 11
An embodiment in which a separate flow of the coating liquid is directed towards a vortex containing the coating liquid contained in the coating chamber, where the vortex is formed around the optical fiber in the coating chamber. The method according to any one of 1 to 10.

Embodiment 12
11. The method according to embodiment 11, wherein the difference between the maximum temperature of the coating liquid in the vortex and the minimum temperature of the coating liquid in the vortex is less than 80 ° C, preferably less than 60 ° C.

Embodiment 13
The method according to embodiment 4 or 5, wherein the sizing die comprises a cone-only die, wherein the cone-only die includes a cone portion and a land portion and does not include a bell portion.

Embodiment 14
11. The method of embodiment 11 or 12, wherein a separate stream of the coating is mixed with the coating of the vortex.

Embodiment 15
A separate stream of the coating solution is described below:
Flow rate over 0.1 cm ³ / s,
Flow rate over 0.2 cm ³ / s,
Flow rate over 0.5 cm ³ / s,
Flow rate in the range of 0.1 cm ³ / s to 20 cm ³ / s,
Flow rate in the range of 0.2 cm ³ / s to 20 cm ³ / s,
The method according to any one of embodiments 1 to 14, wherein the flow rate is selected from the flow rate in the range of 0.5 cm ³ / s to 20 cm ³ / s, and the flow rate is flown in the line drawing direction in the lateral direction.

Embodiment 16
The method according to any one of embodiments 1 to 15, wherein a separate stream of the coating solution is introduced into the coating chamber at an inlet configured for the separate stream of the coating solution.

Embodiment 17
The coating liquid is removed from the coating chamber at an outlet configured for the coating liquid, where the outlets are from the inlet of the optical fiber to the coating chamber and the outlet of the optical fiber from the coating chamber. 16. The method of embodiment 16, which is spaced apart from each other.

Embodiment 18
17. The method of embodiment 17, wherein the coating liquid is removed at the outlet in an amount substantially equal to the amount supplied to the inlet.

Embodiment 19
A separate stream of the coating liquid is supplied to the coating chamber at a temperature lower than the average temperature of the coating liquid in the vortex, preferably here, a separate stream of the coating fluid supplied to the coating chamber. 11. The method of embodiment 11, 12 or 14, wherein the flow temperature is at least 5 ° C. lower than the average temperature of the coating solution in the vortex.

20th embodiment
17. The method of embodiment 17 or 18, further comprising returning the coating liquid removed at the outlet to the coating chamber.

21st embodiment
The coating liquid is as follows:
Flow rate over 0.1 cm ³ / s,
Flow rate over 0.2 cm ³ / s,
Introduced at said inlet and / or said at a flow rate selected from one or more of a flow rate greater than 0.5 cm ³ / s or a flow rate in the range 0.1 cm ³ / s to 20 cm ³ / s. The method according to any one of embodiments 16 to 18 or embodiment 20, which is removed from the outlet.

Embodiment 22
Further comprising the step of drawing the optical fiber through a second coating chamber containing the second coating liquid, preferably the optical fiber is subjected to the same treatment in the second coating chamber as in the first coating chamber. The method according to any one of embodiments 1 to 21.

23rd Embodiment
The method according to any one of embodiments 3 to 6, embodiment 8 or embodiment 13, wherein the guide die does not contain the coating liquid.

Embodiment 24
A coated optical fiber obtained according to any one of embodiments 1 to 23.

25th embodiment
A system for processing optical fibers, the system of which is
One or more coating chambers comprising a fiber inlet and a fiber outlet for holding a coating solution for coating an optical fiber, wherein the fiber inlet and the fiber outlet are optical fibers passing through the coating chamber. The coating chamber that determines the drawing direction of
An inlet for delivering the flow of the coating liquid to the coating chamber, wherein the inlet is configured to deliver the flow of the coating liquid in a direction across the drawing direction. ,
It is provided with an outlet for removing the coating liquid from the coating chamber.
The system, wherein the inlet and the outlet are different from the fiber inlet and the fiber outlet.

Embodiment 26
25. The system of embodiment 25, wherein the outlet is configured to remove a stream of the coating liquid from the coating chamber.

Embodiment 27
25. The system of embodiment 25 or 26, wherein the fiber inlet comprises a guide die for guiding the optical fiber into the coating chamber, and the fiber outlet comprises a sizing die that delivers the optical fiber from the coating chamber.

Embodiment 28
The system according to any one of embodiments 25 to 27, further comprising a second coating chamber.

Embodiment 29
28. The system of embodiment 28, wherein the fiber outlet is an inlet to the second coating chamber.

30th embodiment
The system according to any one of embodiments 25 to 29, wherein the cross-sectional dimension of the inlet exceeds 30% of the distance between the fiber inlet and the fiber outlet.

Embodiment 31
The system according to any one of embodiments 25 to 29, wherein the cross-sectional dimension of the inlet exceeds 50% of the distance between the fiber inlet and the fiber outlet.

Embodiment 32
The system according to any one of embodiments 25 to 29, wherein the cross-sectional dimension of the inlet exceeds 70% of the distance between the fiber inlet and the fiber outlet.

Embodiment 33
The system according to any one of embodiments 25 to 29, wherein the cross-sectional dimension of the inlet is in the range of 30% to 100% of the distance between the fiber inlet and the fiber outlet.

Embodiment 34
It ’s a method of processing optical fiber.
The step of drawing the optical fiber through the guide die into the pressure coating chamber containing the first coating liquid at the drawing speed,
The step of forming the meniscus of the first coating liquid on the optical fiber in the pressure coating chamber, and
A step of forming a boundary layer on the optical fiber in the pressure coating chamber, wherein the boundary layer contains the first coating liquid, begins with the meniscus, and the boundary layer is from the guide die. With steps, with a thickness that increases with increasing distance,
In the step of drawing the optical fiber through the pressure coating chamber to the sizing die at the drawing speed, the sizing die causes the boundary layer to shrink, and the shrinkage occurs from the boundary layer to the pressure coating chamber. A step that causes the release of the first coating solution to and the formation of a vortex containing the first coating solution in the pressure coating chamber.
A step of drawing the optical fiber through the sizing die at the drawing speed, wherein the optical fiber exits the sizing die at the surface layer of the first coating liquid.
A method comprising the step of laterally flowing the first coating liquid in the coating chamber through a channel disposed between the guide die and the sizing die.

10 Optical fiber 20 Coating chamber 30 Guide die outlet 40 Sizing die 50 Sizing die outlet 60 Boundary layer 70 Tapered surface 80 Part of coating fluid 110 Optical fiber 120 Coating chamber part 130 Guide die outlet 140 Sizing die 150 Sizing die outlet 160 Vortex boundary 170 Introduction of coating liquid 180 Removal of coating liquid 210 Optical fiber 220 Coating chamber 230 Guide die outlet 240 Sizing die 250 Sizing die outlet 260 Outer boundary 270 Introduction of coating liquid 280 Removal of coating liquid 300 Coating unit 305 Optical fiber 310 Guide die 315 Coating chamber 320 sizing die 325 downstream coating unit 330 inlet 335 exit 340 lateral 345 lateral 350 guide die 355 coating chamber 360 sizing die 365 inlet 370 outlet 375 lateral 380 lateral 400 coating unit 405 optical fiber 410 guide die 415 coating chamber 425 Coating Chamber 430 Sizing Die 435 Inlet 440 Exit 445 Lateral 450 Lateral 455 Inlet 460 Exit 465 Lateral 470 Lateral

Claims (21)

A method of processing optical fiber, which is as follows:
A step of drawing an optical fiber in a drawing direction along a process path through a coating chamber, wherein the coating chamber contains a coating liquid, the coating liquid coats the optical fiber, and the optical fiber is from a guide die to the coating chamber. Steps and exits the coating chamber from the sizing die
A step of guiding a separate flow of the coating liquid through the coating chamber in a direction across the line drawing direction of the optical fiber, wherein the separate crossing flow of the coating liquid is the process path in the line drawing direction. The separate cross-sectional flow of the coating liquid across and through and mixed with the coating liquid contained in the coating chamber is as follows:
Flow rate over 0.1 cm ³ / s,
Flow rate over 0.2 cm ³ / s,
Flow rate over 0.5 cm ³ / s,
Flow rate in the range of 0.1 cm ³ / s to 20 cm ³ / s,
Flow rate in the range of 0.2 cm ³ / s to 20 cm ³ / s,
A step of flowing in the crossing direction at a flow rate selected from a flow rate in the range of 0.5 cm ³ / s to 20 cm ³ / s, and
Including
A method of introducing a separate cross-sectional flow of the coating liquid into the coating chamber at the inlet and removing the separate cross-sectional flow of the coating liquid from the coating chamber at the outlet opposite the inlet. The method of claim 1, wherein the coating chamber is pressurized. The pressurized coating chamber is described below:
Pressure above 1.01 bar (0 psig) (0 kPaG),
A pressure of at least 1.02 bar (0.10 psig) (about 690 PaG),
A pressure of at least 1.08 bar (1.0 psig) (about 6.9 kPaG),
A pressure of at least 1.36 bar (5.0 psig) (about 34 kPaG),
A pressure of at least 1.70 bar (10 psig) (about 69 kPaG),
Pressures in the range of 1.02 bar (0.10 psig) (about 690 PaG) to 21.70 bar (300 psig) (about 2.07 MPaG),
Pressures in the range of 1.08 bar (1.0 psig) (about 6.9 kPaG) to 16.53 bar (225 psig) (about 1.55 MPaG),
2. The method of claim 2, wherein the method has a pressure selected from a pressure in the range of 1.36 bar (5.0 psig) (about 34 kPaG) to 14.80 bar (200 psig) (about 1.38 MPaG). 13. Method. The one according to any one of claims 1 to 4, wherein the guide die or the sizing die includes a cone-only die, and the cone-only die includes a cone portion and a land portion and does not include a bell portion. Method. The guide die includes a bell portion, a taper portion and a land portion, or the guide die includes a cone-only die, wherein the cone-only die includes a cone portion and a land portion and a bell portion. The method according to any one of claims 1 to 5, which does not include. Claims 1 to 6 draw the optical fiber along the process path at a drawing speed in the range of at least 30 m / s, or at least 40 m / s, or at least 50 m / s, or 40 m / s to 80 m / s. The method described in any one of the above. The method according to any one of claims 1 to 7, further comprising a step of curing the coating liquid after the optical fiber exits the sizing die. The method of claim 8, wherein the curing is achieved with an LED light source. A separate transverse flow of the coating liquid is directed towards a vortex containing the coating liquid, where the vortex is composed of the coating liquid in the coating chamber and the optical fiber in the coating chamber. The method according to any one of claims 1 to 9, which surrounds. 10. The method of claim 10, wherein the difference between the maximum temperature of the coating liquid in the vortex and the minimum temperature of the coating liquid in the vortex is less than 80 ° C or less than 60 ° C. 10. The method of claim 10 or 11, wherein the separate transverse flow of the coating liquid mixes with the coating liquid of the vortex. The method according to any one of claims 1 to 12, wherein the inlet and the outlet are arranged at intervals from the guide die and the sizing die. 13. The method of claim 13, wherein the outlet removes the separate cross-sectional flow of the coating solution in an amount approximately equal to the amount supplied to the inlet of the coating chamber. 14. The method of claim 14, further comprising returning the coating liquid removed at the outlet to the coating chamber. The method of any one of claims 10-12 , wherein the separate lateral flow of the coating liquid supplied at the inlet has a temperature lower than the average temperature of the coating liquid in the vortex. .. 16. The method of claim 16, wherein the temperature of the coating liquid at the inlet is at least 5 ° C. lower than the average temperature of the coating liquid in the vortex. The separate lateral flow of the coating liquid is described below:
Flow rate over 0.1 cm ³ / s,
Flow rate over 0.2 cm ³ / s,
Introduced at said inlet and / or said at a flow rate selected from one or more of a flow rate greater than 0.5 cm ³ / s or a flow rate in the range 0.1 cm ³ / s to 20 cm ³ / s. The method according to any one of claims 13 to 17, wherein the method is removed from the outlet. The method of any one of claims 1-18, further comprising the step of drawing the optical fiber through a second coating chamber, wherein the second coating chamber comprises a second coating liquid. 19. The method of claim 19, further comprising exposing the optical fiber to a lateral flow of the second coating liquid in the second coating chamber. A system for processing optical fibers, the system of which is
A coating chamber that holds a coating solution for coating an optical fiber, wherein the coating chamber defines a drawing direction for drawing the optical fiber through the coating liquid in the coating chamber. With a coating chamber and a fiber optic outlet,
An inlet for delivering the lateral flow of the coating liquid to the coating chamber, wherein the lateral flow of the coating liquid flows in a direction crossing the line drawing direction.
An outlet for removing the lateral flow of the coating liquid from the coating chamber,
Equipped with
The inlet and the outlet are different from the fiber inlet and the fiber outlet, and the inlet is as follows:
Flow rate over 0.1 cm ³ / s,
Flow rate over 0.2 cm ³ / s,
Flow rate over 0.5 cm ³ / s,
Flow rate in the range of 0.1 cm ³ / s to 20 cm ³ / s,
Flow rate in the range of 0.2 cm ³ / s to 20 cm ³ / s,
It is configured to supply the lateral flow of the coating solution at a flow rate selected from a flow rate in the range of 0.5 cm ³ / s to 20 cm ³ / s.
A system in which the outlet and the inlet are located on the coating chamber between the fiber inlet and the fiber outlet, with the outlet located opposite the inlet.

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