JPH10287445A - Radiation-curable optical glass fiber coating composition containing polyalkylsiloxane additive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an improved radiation-curable optical glass fiber coating composition, keeping good adhesion to a glass surface under high humidity conditions and showing a sufficiently low friction with the fiber to facilitate the ribbon to be peeled from the fiber, by making the composition include a non-reactive polyphenylalkylsiloxane as a premix component in a radiation- curable oligomer. SOLUTION: This coating composition is a liquid, radiation-curable one containing a radiation-curable oligomer as a premix component, and is used to coat, when cured, an internal primary optical glass. It has a polymer main chain, at least one radiation-curable functional group, and non-reactive polyphenylalkylsiloxane. When cured, it shows a fiber pull-out friction of approximately 18 or lower, debonding time of longer than 24 h before it is debonded to half when immersed in water, and wet and dry adhesiveness of higher than 10 g. The composition can be optionally incorporated with an organofunctional silane adhesion promoter, reactive diluent or photoinitiator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to improved radiation curable internal primary optical glass fiber coating compositions containing non-reactive polyphenylalkylsiloxane additives, optical glass fibers coated therewith, and made from those coated fibers. To a fabricated optical glass fiber assembly. In particular, the present invention provides an improved combination of adhesion of the coating to the glass fiber surface after curing, especially under high wet conditions, and good optical fiber ribbon strippability. To provide an internal primary coating composition.

[0002]

BACKGROUND OF THE INVENTION Radiation curable coatings and other types of protective materials are widely used in the optical fiber industry during the manufacture of optical fibers and cables. The optical glass fibers are usually coated with at least one radiation-curable coating immediately after the glass fibers have been produced in the lifting tower, so as to maintain the initial properties of the glass fibers. Immediately after the coating is applied to the fibers, the coating is exposed to radiation (typically ultraviolet light) to cure quickly. Industrially, it is required to increase the production speed, and therefore, high-speed curing of the coating composition is essential. The radiation-curable matrix material further protects the individual yarns of the fibers and bundles the fiber yarns together to form an optical fiber ribbon,
It can be a fiber optic cable and associated structure.

[0003] Because of the desire for various competing properties in the coated tissue, multi-layer polymer coatings are commonly used in optical fiber manufacturing. They typically have a soft inner primary coating that directly contacts the glass fiber and provides a cushion,
It has a strong outer primary coating (sometimes called a secondary coating) that provides a more durable exterior for the glass fibers. In cable assemblies, it is often desirable to provide a colored coating to facilitate identification of a particular optical fiber among many fibers. This can be achieved by various methods known in the art, for example, by applying radiation-curable inks or solvent-containing lacquers for coloring or overcoating the outer primary coating.

Examples of radiation-curable primary coatings are described, for example, in US Pat. No. 5,336,360 to Coady et al.
No. 563. For further features of optical fiber coating technology, see Nolan et al., U.S. Patent No. 5,199,098; Urruti et al., U.S. Patent No. 4,923,915;
imura) et al., U.S. Patent No. 4,720,529;
And U.S. Pat. No. 4,47 by Taylor et al.
No. 4,830.

[0005] The inner primary coating is usually a relatively soft coating having a low glass transition temperature (Tg) to cushion the glass fibers and provide resistance to microbending. Micro-bending can result in an attenuation of the signal-carrying capacity of the coated optical glass fiber and is therefore undesirable. The outer primary coating is typically a stiffer coating that provides the desired resistance to handling forces that are encountered when the coated fiber is cabled.

[0006] Optical fiber assemblies provide a modular mechanism for multi-channel transmission, which simplifies the production, installation and management of optical glass fibers by eliminating the need to handle individual optical glass fibers. Typically,
A plurality of coated optical glass fibers are bonded together in a matrix material to form, for example, a ribbon-like assembly. For example, the matrix material can be used to encase optical glass fibers or to end bond optical glass fibers together.

When one or more optical fibers in the assembly need to be melt bonded to another optical fiber or connector,
The edges of the matrix layer are removed and the individual optical fibers are separated. It is desirable that the inner and outer primary coatings of the individual fibers be removed simultaneously with the matrix material to provide a bare surface portion of the optical glass fibers. This method is typically referred to as "ribbon stripping". Preferably, the physical properties of the coating and the matrix material are such that the matrix material and the primary coating can be removed from the fiber assembly as a cohesive body.

[0008] Ribbon stripping is typically performed by sandwiching the end of the ribbon assembly between two heated plates and then removing the heat softened matrix material and coating. Ideally, the adhesion and fiber friction properties of the inner primary coating to the fiberglass surface are such that the coating material is easily removed, leaving a clean bare optical fiberglass surface with virtually no residue. It is.

The need for good strippability is disclosed by Ansel et al. In US Pat. No. 4,472,472.
No. 021, the patent relates to a radiation-curable coating composition which is used in particular to reduce the adhesion of the radiation-cured coating to optical glass fibers, thereby improving peelability. In particular, this patent discloses that radiation-containing organopolysiloxanes having multiple hydroxy end groups attached to some of the silicon atoms in the polysiloxane chain by carbon-silicon bonds contain about 2-20% of the coating composition. It states that the curable polyethylene organic compound is modified. It is stated that while the remaining non-hydroxyl terminal substituents of the polysiloxane are preferably methyl, they may be ethyl or butyl or even phenyl or toluyl groups. Dow Corning allegedly a dimethylpolysiloxane polycarbinol graft polymer
DC-193 is particularly preferred. Another preferred polysiloxane exemplified in this patent is the dimethylpolysiloxane polycarbinol graft polymer sold by Dow Corning as DC-57 and DC-190.

US Pat. No. 5,373,578 to Parker et al. Also relates to the strippability of optical glass fibers, column 6, lines 43-47, which severely degrades adhesion to glass fibers. Choosing an appropriate additive to facilitate removal of the primary coating from the glass fiber without having to do so is a considerable problem, especially since both properties are required and they are likely to be mutually exclusive. It is recognized to be a problem. Parker et al. Discuss organopolysiloxane additives described in U.S. Pat. No. 4,472,021 having a plurality of hydroxy end groups that are effective in improving strippability. However, they note that coatings containing this additive have poor adhesion to glass fibers, and can cause exfoliation and subsequent ingress of water, especially when exposed to high humidity, which erodes the glass surface and reduces tensile strength. Admits that it will be reduced. Parker et al. Instead proposes adding 1-20% of a non-crosslinked hydrocarbon component to improve strippability while still maintaining adhesion to glass fibers.

[0011] Water can have a very detrimental effect on optical glass fibers, weakening the fibers and reducing their fatigue resistance. Moisture from the atmosphere can weaken glass fibers and cause their ultimate destruction. Therefore, the glass fibers must be protected from exposure to water or moisture, which is also one of the purposes of the primary coating. However, this moisture may cause exfoliation of certain inner primary coatings from the glass surface, thereby exposing the glass surface to moisture, particularly in the above-mentioned US Pat. No. 4,472,472.
Such occurs when the adhesion of the inner primary layer to the glass is intentionally reduced to promote clean strippability of the ribbon, as described in U.S. Pat. No. 021.

Various methods have been proposed to prevent the degradation of optical glass fibers in the presence of moisture. For example, U.S. Patent No. 4,849, Bishop et al.
No. 462 discloses various organic compounds as adhesion promoters in order to improve the adhesion between the coating composition and the glass fiber surface, especially after exposure to a humid atmosphere. It teaches formulating a functional silane. Although these organofunctional silane modified compositions improve the dry and wet adhesion of the coating, they may also substantially increase the friction of the fibers, which has a negative effect on the strippability of the ribbon. Have given.

As described in Bishop et al., The use of organofunctional silanes in coatings improves the wet adhesion of coatings applied to optical glass fibers, but the organofunctional silanes do not Does not significantly improve the ability to maintain glass strength. Thus, US Pat. No. 5,502,1
No. 45 and 5,595,820 propose an improved coating composition wherein the degradation rate of the coated glass fibers is such that at least the inner primary coating has a hydrolyzable alkoxy-substituted poly (siloxane). Is slowed by blending

However, the demands on the performance of optical fiber coatings continue to grow, becoming more stringent each year, and further improvements in the overall properties of the coatings are required. In particular, there is currently a need for a coating composition that provides good ribbon stripping properties, which prevents peeling of the inner primary coating from the glass fiber surface, especially in the presence of moisture, and is not limited to water and air. Even the moisture must be balanced against the critical and ever-competitive need to protect glass fibers from its deleterious effects. Thus, the inner primary coating provides sufficient adhesion to the glass fiber surface, provides an effective barrier to moisture transmission, promotes wet adhesion and glass strength maintenance, and still has low fiber friction to facilitate stripping of the ribbon. It is highly desirable to have It has heretofore been overlooked to find a coating composition that has the right balance between good wet adhesion (to avoid peeling) and low fiber friction (to achieve clean ribbon peelability).

[0015]

The present invention, when properly cured, maintains good adhesion to glass surfaces under high humidity conditions, protects glass fibers from the detrimental effects of water penetration, and strips ribbon. It is to satisfy the need for improved radiation-curable optical glass fiber coating compositions that provide a combination of improved properties, including having sufficiently low fiber friction to facilitate.

[0016]

SUMMARY OF THE INVENTION This combination of improved properties provides about 0.1-30% by weight of a known type of radiation-curable inner primary coating composition prior to its application and curing. It was unexpectedly discovered that this could be achieved by adding a non-reactive polyphenylalkylsiloxane. This non-reactive polyphenylalkylsiloxane additive is believed to be particularly effective when added to radiation-curable glass fiber coatings containing organofunctional silane adhesive promoters.

The present invention further provides coated optical glass fibers having an inner primary coating formed by applying the improved coating composition of the present invention and in-situ radiation curing, as well as such coated optical glass fibers. And a ribbon assembly consisting of a plurality of. The resulting coated optical glass fibers and ribbon assemblies made therefrom have improved ribbon peelability, and the present invention relates to peeling under high humidity conditions, fiber fatigue and other harmful effects of water according to the present invention. Are less prone to these than equivalent coatings made from compositions without the non-reactive polyphenylalkylsiloxane additive.

Accordingly, the present invention is directed broadly to a liquid radiation-curable coating composition used to provide an internal primary optical fiberglass coating upon curing, comprising as a premix component:
A radiation-curable oligomer having a polymer backbone and at least one radiation-curable functional group, and a non-reactive polyphenylalkylsiloxane, cured and tested according to the test methods detailed in the Examples, wherein: Provides a coating composition having a combination of properties of fiber pull-out friction of 18 or less, (b) a water soak release time of greater than 24 hours to 1/2 release, and (c) wet and dry adhesion of greater than 10 g force. .

The present invention further relates to a liquid radiation curable coating composition for forming an internal primary optical glass fiber coating, wherein the premix component comprises (A) a polymer backbone and at least one radiation curable functional group. A radiation curable oligomer having: (B) an organofunctional silane adhesion promoter; and (C) a non-reactive polyphenylalkylsiloxane, wherein the components cure the composition. (A) a fiber pull-out friction of about 18 or less, (b) 1 /
2 Provides a coating composition that is present in an amount effective to have a combination of properties of water immersion peel time of greater than 24 hours to peel, and (c) wet and dry adhesion of greater than 10 g force.

The present invention further relates to a novel liquid radiation-curable composition for protecting optical fibers, wherein the premix component comprises (A) a polymer main chain and at least one polymer bonded to the polymer main chain. At least one radiation-curable oligomer having a radiation-curable functional group, (B)
Optionally, at least one organofunctional silane adhesion promoter, and (C) an effective amount of at least one non-reactive polyphenylalkylsiloxane; (D) optionally, at least one reactive diluent; And (E)
Optionally, providing a composition comprising an effective amount of at least one photoinitiator.

In particular, the present invention relates to a novel liquid radiation-curable composition for protecting optical glass fibers, wherein (A) a hydroxy-functional monomer having ethylenic unsaturation, a polyisocyanate, And an oligomer that is the reaction product of a polyol, (B) at least one organofunctional silane adhesion promoter, (C)
An effective amount of at least one non-reactive polyphenylalkylsiloxane, (D) optionally a reactive diluent comprising a polymerizable monofunctional vinyl monomer, and (E) optionally an effective amount of A polymerization initiator.

More particularly, the present invention relates to a novel liquid radiation-curable composition which, when cured, is used to provide an internal primary optical fiberglass coating, as a premix component,
(A) from about 10% to about 90% by weight of at least one radiation curable urethane (meth) acrylate oligomer, comprising an oligomer backbone, at least one urethane linking group, and at least one radiation curable endblocker. Oligomers having groups, (B) at least one organofunctional silane adhesion promoter, (C) about 0.1% by weight
From about 10% to about 9% by weight of at least one non-reactive polyphenylalkylsiloxane of (D)
A composition comprising 0% by weight of at least one reactive diluent, and (E) optionally an effective amount of at least one photoinitiator.

The present invention can also be extended to coated optical glass fibers and coated optical glass fiber aggregates having an inner primary coating formed from the radiation curable coating composition of the present invention, such as ribbon aggregates.

According to the present invention, there is provided a premix component comprising (A)
Oligomer backbone, at least one urethane linking group,
And at least one radiation-curable urethane (meth) acrylate oligomer having at least one radiation-curable end-capping group, from about 10% to about 90% by weight, and (B) at least one organofunctional silane adhesion promoter. The liquid radiation-curable coating composition containing the composition, applied on the optical glass fiber, and cured by in-situ, the radiation-curable inner primary coating on the optical glass fiber ribbon peelability and wet adhesion and Prior to application and curing, the liquid coating composition comprises (C) from about 0.1% to about 30% by weight of at least one non-reactive polyphenylalkylsiloxane;
Is also provided.

As used herein, the term "premix component" refers to a designated component added to a composition prior to mixing with, and preferably reacting with or interacting with, the other components of the composition. I do.

The present invention relates to a coating composition for forming an internal primary coating layer directly on the glass surface of an optical fiber,
It is also contemplated that the coated optical fibers in use additionally include at least one outer primary (ie, secondary) layer. The present invention provides continuous and simultaneous (wet-on-wet)
-on-wet)], and can be applied to various optical fiber coating techniques including both cured tissues. In the former case,
The inner and outer primary coatings are applied and cured sequentially (one after the other) in separate curing stages, whereas in the latter the coatings are each successively coated before curing and then one curing stage Curing at the same time.

[0027]

DETAILED DESCRIPTION OF THE INVENTION Radiation curable compositions for forming an inner primary coating on optical glass fibers (hereinafter referred to as "inner primary compositions") are now well known in the art. Internal primary compositions suitable for use in the present invention include:
As described in more detail below, it includes at least one radiation-curable oligomer, optionally at least one reactive diluent, a polymerization initiator, and / or an organofunctional silane adhesion promoter. The radiation-curable oligomer typically has a polymer backbone and at least one radiation-curable functional group attached to the polymer backbone. The advantageous combination of properties of the present invention is achieved by adding an effective amount of at least one non-reactive polyphenylalkylsiloxane to the internal primary composition.

Non-reactive polyalkylphenylsiloxanes suitable for use in the present invention have the formula (I):

[0029]

Embedded image

Wherein each R is independently (C 1 -C 1)
2) represents an alkyl group, a phenyl group, or another non-reactive group defined below, wherein n is 2 or more, provided that the average mole% of the phenyl R group in the polyalkylphenylsiloxane component (hereinafter referred to as “phenyl mole% ) Is at least about 10 mol%. ] Having a siloxane repeating unit having the general structure of The phenyl mole percent is preferably at least about 20 mole percent, more preferably in the range of about 20 to about 60 mole percent. The phenyl group may be substituted or unsubstituted, but is preferably unsubstituted. Each R is preferably a (C1-12) alkyl or phenyl group.

The number of repeating units n is usually an integer greater than 2, but when the polyalkylphenylsiloxane component is a mixture of such siloxanes of different lengths, n represents the average number of siloxane repeating units. And therefore need not be an integer. n is preferably in the range of about 10 to about 100, more preferably in the range of about 10 to 80. For the R substituents along the polymer chain, the number n of each unit may be the same or the number n of units may be different.
The non-reactive polyphenylalkylsiloxane of the present invention comprises
It may be in the form of a block copolymer falling within the limits of formula (I) as defined above.

As used herein, the term "non-reactive" refers to a polyalkylphenylsiloxane suitable for use in the present invention which is cured by radiation or coated under conditions which produce and cure the composition. It means that it does not contain any R, X, or Y groups that react or hydrolyze with other components of the composition. Thus, in the polysiloxane represented by formula (II), the end-capping groups X and Y are independently selected from groups suitable as siloxane substituents, and they are non-reactive:

[0033]

Embedded image

Preferably, X and Y are independently 1-12
Is selected from linear or branched alkyl, cycloalkyl, or aryl groups having three carbon atoms. More preferably, X and Y are independently selected from (C 1 -C 12) alkyl or phenyl, most preferably methyl, ethyl or propyl.

When R is (C 1 -C 12) alkyl, it is preferably methyl, ethyl or propyl, but preferably a methyl side group. In a preferred structure of formula (III):

[0036]

Embedded image

Me represents methyl, each R independently represents phenyl or methyl, wherein phenyl mole% is at least 20 mole%, and X, Y and n are as defined above.

In another preferred embodiment, the polymethylphenylsiloxane has the following formula (IV):

[0039]

Embedded image

Me is methylene and X, Y and n are as given above.

(CH_Three)_TwoSiO and up to 50 mol%
CH_Three(C₆H_Five) SiO or (C ₆H_Five)_TwoSiO
And a copolymer with
Commercially available as C550 and DC710 silicone fluids
Polyphenylalkylsiloxanes are particularly useful in the present invention.
It has been found suitable for use in

The polyalkylphenylsiloxane is preferably present in the resin composition in an amount of about 0.1 to about 30% by weight, more preferably about 0.5% to about 10% by weight.
And most preferably in the range of about 2-6% by weight.

The radiation-curable optical fiber coating used in the present invention comprises at least one radiation-curable oligomer,
And optionally at least one reactive diluent. The radiation-curable oligomer has a polymer backbone and at least one radiation-curable functional group attached to the polymer backbone. The polymer backbone may include one or more polymers or copolymers.

[0044] The polymer backbone may be composed of one or more polymers or copolymers. The type and molecular weight of the polymer (s) and / or copolymer (s) that may be present in the polymer backbone will depend on the particular application. Based on the description herein, one of ordinary skill in the art will appreciate the type and molecular weight of the polymer (s) or copolymer (s) used to provide the desired properties of the radiation cured resin, such as Tg and modulus. Could be selected.

Suitable examples of polymers and copolymers include, but are not limited to, polyethers, polyesters, polycarbonates, polyolefins, polyurethanes, and copolymers thereof. Preferably,
The polyether or a copolymer of the polyether and at least one of the other polymers listed above is used as the polymer backbone of the radiation-curable oligomer.

The oligomer has at least one radiation-curable functional group. At least some of the oligomer components have at least two radiation-curable groups, and the average number of radiation-curable groups per oligomer in the oligomer component is preferably at least about 1.8, and more preferably At least about 2.

The radiation-curable functional groups used are actinic radiation
Any functional group capable of polymerizing when exposed to (actinic radiation). Suitable such groups are now well known and are within the skill of those in the art.

Commonly used radiation-curable functional groups include:
It has ethylenic unsaturation that can be polymerized by radical polymerization or cationic polymerization. Particular examples of suitable ethylenically unsaturated are groups including acrylates, methacrylates, styrenes, vinyl ethers, vinyl esters, N-substituted acrylamides, N-vinylamides, maleate esters, and fumarate esters. Ethylenic unsaturation is preferably provided by groups containing acrylate, methacrylate, or styrene functionality.

Another type of radiation-curable functional group commonly used is, for example, an epoxy group, or a thiol-ene,
Or by an amine-ene system. Epoxy groups can be polymerized by cationic polymerization, whereas thiol-ene and amine-ene systems are usually polymerized by radical polymerization. Epoxy groups can be homopolymerized, for example. In thiol-ene and amine-ene systems, for example, polymerization can be carried out between groups containing allylic unsaturation and groups containing tertiary amines or thiols.

The selected type of radiation-curable oligomer should provide a cured internal primary coating having a Tg of less than about -20 ° C, preferably less than about -27 ° C.
Generally, the higher the molecular weight of the radiation curable oligomer, the lower the Tg of the cured internal primary coating. This is because the crosslink density decreases as the molecular weight increases. Suitable theoretical number average molecular weights are from about 1000 to about 1
It has been found to be between about 000 and preferably between about 1000 and about 8000. The theoretical number average molecular weight is determined by calculating the number average molecular weight of the ideal oligomer structure formed from the reactants, reaction conditions, and reaction stoichiometry used.

It is believed that the benefits of the present invention can be obtained by adding a non-reactive polyphenylalkylsiloxane to a very wide variety of radiation curable inner primary coating compositions. However, it is believed that the present invention is particularly applicable to such coatings based on urethane (meth) acrylate oligomers, optionally including at least one reactive diluent and / or organofunctional silane adhesion promoter. Can be

[0052] Urethane acrylate oligomers are preferred over urethane methacrylate oligomers. They are the reaction products of polyols (forming oligomer backbones), polyisocyanates (linking oligomer backbones and end-capping groups), and end-capping radiation-curable acrylate groups (polymerizing by exposure to radiation). You can make things. The oligomer synthesis for the inner primary coating is described, for example, in the method described in US Pat. No. 5,336,563 to Coady et al., A complete description of which is incorporated herein by reference. Can be performed. The synthesis conditions are usually adjusted so that the oligomer has on average about 1-2 polyol backbone units, preferably about 1 polyol unit per oligomer molecule. Conventional oligomer synthesis methods known in the art can be used.

The synthesis described in US Pat. No. 5,336,563 can be used with an outer primary (secondary) coating matrix material and the improved inner primary coating of the present invention. It can also be used to make oligomers for other protective materials. Such coatings are described, for example, in US Pat.
22,465 and 4,514,037, the complete descriptions of which are incorporated herein by reference.

The oligomer may comprise from about 10% to about 10% by weight of the total composition.
It can be present in an amount of about 90%, preferably about 40% to about 80%, more preferably about 45% to about 70% by weight. One skilled in the art can adjust the amount of oligomer in view of the final requirements. For example, as the amount of the oligomer used increases, the curing rate tends to increase.

The urethane acrylate oligomer can be, for example, an oligomer having a main chain of polyether, polyester (including polycaprolactone), polycarbonate, hydrocarbon (saturated and unsaturated), and silicone unit. Preference is also given to polycarbonate- and polyether-based oligomers and mixtures thereof. The oligomer may include a block copolymer and a random copolymer structure.

The oligomer can be synthesized using at least one kind of polyol oligomer compound, preferably a diol, which functions as an oligomer backbone. The oligomer (s) forming the main chain may have an amine function (s). The main-chain hydroxyl groups form urethane bonds when reacted with polyisocyanates during oligomer synthesis, whereas the amine groups form urea bonds when reacted with polyisocyanates. Urea bonds can provide improved adhesion and greater stiffness. Thus, the relative amounts of urethane and urea linkages can be used to adjust the properties of the oligomer and the total coating composition.

In one embodiment for the inner primary coating, the oligomer is a block copolymer oligomer,
It has a main chain of both polyether and polycarbonate. Each main chain block is, for example, about 750 to 3,000
It can have a molecular weight of g / mol. In another aspect, the oligomer is a block copolymer made from a mixture of polyhexyl carbonate and polypropylene glycol, among other components. In yet another embodiment, a copolymer polyether is used based on the copolymerization of tetrahydrofuran and methyltetrahydrofuran.

The urethane acrylate oligomer further has at least one urethane linking group that can be formed using a polyisocyanate linking compound. Polyisocyanate bonding group compounds are well known in the field of optical fiber coating, and their selection is not particularly limited. During oligomer synthesis, the polyisocyanate linking compound can link the polyol backbone compound itself or to another type of polyol backbone compound, or a radiation-curable end group compound. The polyisocyanate bonding group compound is preferably a diisocyanate compound, but higher isocyanates such as, for example, triisocyanates can also be used.

The polyisocyanate is also preferably aliphatic, but may contain certain aromatic polyisocyanates. Aromatic isocyanate compounds can have an undesirable yellowing of the coating, but in small amounts can tolerate aromatic groups in a given composition.

In some cases, polymeric isocyanates may be useful. However, the polyisocyanate compound preferably has, for example, 4 to 20 carbon atoms. The molecular weight of the polyisocyanate may be less than about 1,000 g / mol, but is preferably less than about 500 g / mol.

Examples of diisocyanates include diphenylmethylene diisocyanate, hexamethylene diisocyanate, cyclohexylene diisocyanate, methylene dicyclohexane diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, m-phenylene diisocyanate, 4-chloro-1,3- Phenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1,5-naphthylene diisocyanate, 1,4-
Tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,10-decamethylene diisocyanate, 1,4-cyclohexylene diisocyanate, tetramethyl xylene diisocyanate, and polyalkyl oxide and polyester glycol diisocyanates, for example, each terminated with TDI Polytetramethylene ether glycol, and TDI-terminated polyethylene adipate.

[0062] Toluene diisocyanate is a preferred example of an inexpensive aromatic linking compound. Isophorone diisocyanate is a preferred aliphatic linking compound.

The urethane linkage can be, for example, a dibutyltin dilaurate or diazabicyclooctane crystal,
It can be generated using conventional urethanization catalysts known in the art.

The oligomer further has at least one radiation-curable end-capping group. End-blocking means that the oligomer has a radiation-curable end point at its molecular chain end. The oligomer preferably has two radiation-curable end-capping groups. The choice of compounds used to form these terminal groups is not particularly limited, and those compounds are well known in the art.

Generally, the end-capping group is, for example, 500 g
/ Mol, preferably less than about 300 g / mol, formed from at least one monoethylenically unsaturated compound of relatively low molecular weight. Methacrylates and acrylate compounds are preferred for forming terminal blocking groups, and acrylate compounds are particularly preferred. Hydroxyalkyl acrylate compounds are preferred, and hydroxyethyl acrylate is a particularly preferred compound. Other preferred examples include hydroxypropyl acrylate and hydroxybutyl acrylate. End-capping compounds are discussed further in US Pat. No. 5,366,563.

Reactive diluents are well known in the field of optical fiber coatings and their choice need not be particularly limited. In many cases, a mixture of diluent compounds is required for optimal properties. Suitable diluents include in particular (meth) acrylate compounds, with acrylate compounds being preferred.

The diluent serves to reduce the viscosity of the oligomer and serves to adjust the properties of the final coating, for example properties such as refractive index and polarity (moisture absorption). They also serve to adjust the mechanical properties and crosslink density of the composition and determine what the composition is best suited to, for example, whether it is suitable as an inner primary coating, outer primary coating, single coating, or matrix material. Acts as a decision. Aromatic diluents, such as phenoxyethyl acrylate or ethoxylated nonylphenol acrylate, tend to increase the refractive index of the material. Aliphatic diluents such as lauryl acrylate provide hydrophobicity and diluents with long chain alkyl groups also tend to soften the composition. Polar diluents, such as N-vinylpyrrolidone, can improve mechanical properties at room temperature through hydrogen bonding. Multifunctional diluents such as trimethylolpropane triacrylate can increase cure speed and crosslink density.
Since water generally has a deleterious effect on the fibers, the formulation can be adjusted with non-polar diluents that help reduce water absorption. The functional groups present in the reactive diluent can be copolymerized with the radiation-curable functional groups present in the radiation-curable oligomer.

The molecular weight of the diluent compound need not be particularly limited, but is generally less than about 1,000 g / mol. However, the oligomer diluent may have certain oligomeric properties such as repeating ethene-based groups such as ethyleneoxy or propyleneoxy in the alkoxylated alkylphenol acrylate diluent.

The total amount of diluent need not be particularly limited, but will be selected by one skilled in the art to be effective in achieving the advantages of the present invention for a particular application. For example,
The total amount of diluent is from about 10% to about 90% by weight, preferably from about 20% to about 60% by weight, more preferably from about 25% to about 50% by weight.

The reactive diluent can be, for example, a conventional monomer or monomer mixture having acrylate functionality and a C ₄ -C ₂₀ alkyl or polyether moiety. Specific examples of suitable reactive diluents include hexyl acrylate, 2-ethylhexyl acrylate, isobornyl acrylate, decyl-acrylate, lauryl acrylate, stearyl acrylate, 2-ethoxyethoxy-ethyl acrylate, lauryl vinyl ether, 2-ethylhexyl Vinyl ether, N-vinyl formamide, isodecyl acrylate, isooctyl acrylate, vinyl-caprolactam, N-vinyl pyrrolidone, and the like.

Another type of reactive diluent that can be used is a compound having an aromatic group. Specific examples of reactive diluents having aromatic groups include ethylene glycol phenyl ether-acrylate, polyethylene glycol phenyl ether acrylate, polypropylene glycol phenyl ether-acrylate, and alkyl-substituted phenyl derivatives of the above monomers, for example, polyethylene. Glycol nonyl phenyl ether acrylate is included.

The reactive diluent may comprise a diluent having two or more functional groups capable of polymerizing.
Examples of such monomers include ethoxylated bisphenol-A-diacrylate, commercially available as SR349A monomer and supplied by Sartomer, C
₂ -C ₁₈ hydrocarbon - diacrylate, C ₃ -C
₁₈ hydrocarbon triacrylates, their polyether analogs and the like, such as 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, hexanediol divinyl ether, triethylene-glycol diacrylate, pentaerythritol-triacrylate, and Tripropylene glycol diacrylate is included.

Preferred diluents for the primary coating are the alkyl and aromatic acrylate diluents described in US Pat. No. 5,336,563. A particularly preferred diluent system for the present invention is a mixture of isodecyl acrylate and ethoxylated nonylphenol acrylate. Other preferred examples include: V. Krongauz and A.K. J. Included are those listed in J. Appl. Polym. Sci., 57 (1995) 1627-1636 by Tortorello.

After diluting the oligomer with a diluent, the viscosity of the uncured composition at ambient temperature is less than about 12,000 cps, but preferably greater than about 2,000 cps, and is preferably from about 3,000 to about 8,000 cps. It is preferred that Preferably, the viscosity is stable over a long period of time to obtain a long shelf life. Many additives in optical fiber coatings can reduce shelf life and are preferably selected so as not to adversely affect shelf life. One skilled in the art can tailor the viscosity to the particular application technique.

The polyphenylalkylsiloxane additives of the present invention are particularly advantageous for coating compositions that include organofunctional silane adhesion promoters, such as acrylate, amino, or mercaptofunctional silanes. The amount used can be up to 30% by weight, in order to increase the adhesion of the primary coating and to maintain it even when exposed to moisture, but preferably from about 0.1 to about 10%. 5% by weight, more preferably in the range of about 0.3-3% by weight. Suitable types of adhesion promoters for optical fiber coatings are described, for example, in US Pat.
No. 9,462 and 5,146,531. Preference is given to using mercaptopropyltrimethoxysilane.

The rapid production of optical fibers using UV curing requires that a photoinitiator be present in the coating composition. However, when using electron beam curing, the use of a photoinitiator is optional. Photoinitiators are well known in the art to increase the cure rate of optical fiber coatings, and the selection of the appropriate type and amount of photoinitiator is within the skill of those in the art. Conventional photoinitiators can be used, and mixtures of photoinitiators can often provide optimal amounts of surface and overall cure. The total amount of the photoinitiator used is, for example, about 0.1
% To about 10%, preferably about 0.5% to about 5% by weight.

As is known in the art, the photoinitiator is preferably of the type that does not cause yellowing. Examples of suitable photoinitiators include hydroxymethylphenylpropane, dimethoxyphenylacetophenone, 2-methyl-1- [4- (methylthio) -phenyl] -2-morpholino-propane-1,1- (4-isopropylphenyl ) -2-hydroxy-2-methylpropan-1-one, 1- (4-dodecyl-phenyl) -2-hydroxy-2-methylpropan-1-one, diethoxyphenylacetophenone, and the like. Phosphine oxide type photoinitiators, such as benzoyldiarylphosphine oxide photoinitiators [e.g. Lucerin (Lucer by BASF)
in) TPO] has been widely used, especially when pigments are present in the material. Mixtures of photoinitiators can also be used. For example, US Pat. No. 5,146,
Non-yellowing photoinitiators as discussed in US Pat. No. 5,311, may be used. A preferred photoinitiator for the primary coating is 2-hydroxy-2-methyl-1-phenyl-
1-propane and bis (2,6-dimethoxybenzoyl) (2,4,4-trimethylpentyl) phosphine oxide, or a mixture thereof.

Other common additives to radiation curable coating compositions include thermal antioxidants such as sterically hindered phenol or sterically hindered amine light stabilizers. A preferred type of thermal antioxidant is the thiodiethylene cinnamate derivative, Irganox 1305, available from Ciba-Geigy. Thermal antioxidants can be present, for example, in an amount of about 0.1% to 1% by weight.

Other additives that can be used include storage stabilizers, such as butylated hydroxytoluene (BH
T), lubricants and friction modifiers, pigments, photofunctional and light absorbing compounds, catalysts, initiators, lubricants, wetting agents, and leveling agents.

Examples 1-4 and Comparative Examples A and B Synthesis of urethane acrylate oligomers Urethane acrylate oligomers designated as HI- (PTGL2000-I) _2- H were prepared from the following components in the proportions indicated. : Component part Isophorone diisocyanate (IPDI) 10.351 Butylated hydroxytoluene (BHT) 0.090 Dibutyltin dilaurate 0.060 2-hydroxyethyl acrylate (2-HEA) 3.600 PTG-L2000 (copolymer of tetramethylene glycol and methyltetramethylene glycol) 62.882 SR-504A (ethoxylated nonylphenol acrylate) 23.018

Isophorone diisocyanate (IPDI)
Was introduced into a stirred reaction vessel equipped with an air purge and cooling means, to which butylated hydroxytoluene (BHT) and dibutyltin dilaurate were added with stirring.
Next, 2-hydroxyethyl acrylate (2-HEA)
At a constant speed while introducing light into the reactor,
Cooling was applied to the reactor so as not to exceed 0 ° C., after which the resulting mixture was kept at 40 ° C. for 60 minutes. PTG-L
The 2000 copolymer was then stirred into the reactor over a period of 30 minutes with cooling to maintain a temperature of 70-80 ° C and held for 60 minutes. Next, SR-504A
(Etoxylated nonylphenol acrylate) was introduced into the reactor and the final oligomer was held for 30 minutes.

Preparation and Testing of Coating Compositions Four coating compositions were made according to the present invention (Examples 1-4),
Two comparative coating compositions were made according to the conventional method, one without the addition of polysiloxane (Comparative Example A) and the other with the addition of the ethoxylated dimethylsiloxane used in the conventional method (Comparative Example B). ). Each coating was applied to a glass substrate and tested for various properties. Table 1 about them
And described further below.

Comparative Example A HI- (PTGL2000-I) ₂ -H prepared above
The oligomer was mixed with the components shown in Table 1 in the proportions described as Comparative Example A. Ethoxylated nonylphenol acrylate is used as a reactive diluent, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide is used as a photoinitiator, γ-mercaptopyroprooltrimethoxysilane is used as an organofunctional silane, thiodiethylene Bis (3,5-di-t-butyl-4-hydroxyhydrocinnamate) was used as a thermal antioxidant.

Comparative Example B To 98 parts of the composition of Comparative Example A, 2.00 parts of Dow Corning liquid ethoxylated dimethylsiloxane DC193 were added. DC193 is disclosed in the above-mentioned U.S. Pat.
2,021 are preferred polysiloxanes,
It has been identified as a dimethylpolysiloxane polycarbinol graft polymer. This polysiloxane reduces the adhesion of the radiation-cured coating applied to the optical glass fiber, thereby improving peelability,
Added to the radiation curable coating composition of that patent.

Example 1 To 98 parts of the composition of Comparative Example A, 2.00 parts of Dow Corning liquid polyphenylmethylsiloxane designated as DC550 were added.

Example 2 To 98 parts of the composition of Comparative Example A was added 2.00 parts of Dow Corning liquid polyphenylmethylsiloxane designated as DC710.

Example 3 To 96 parts of the composition of Comparative Example A was added 4.00 parts of Dow Corning liquid polyphenylmethylsiloxane designated as DC550.

Example 4 To 94 parts of the composition of Comparative Example A was added 6.00 parts of Dow Corning liquid polyphenylmethylsiloxane designated as DC550.

Test Methods Each of the coating compositions of Examples 1-4 (according to the invention) and Comparative Examples A and B was applied to a glass substrate, cured, and subjected to fiber friction, crack propagation, water Tested for peelability, dry adhesion, and wet adhesion.

Fiber Friction The fiber pull-out friction of the inner primary coating is an evaluation of the fiber friction between the inner primary coating and the bare optical glass fibers. Generally, the lower the fiber pull-out friction of the inner primary coating, the lower the fiber friction between the optical glass fiber and the inner primary coating, the lower the resistance, and the easier it is to remove the inner primary coating from the optical glass fiber more smoothly. Also, the lower the fiber friction, the lower the force applied to the inner primary coating to strip the ribbon. The lower the force applied to the inner primary coating, the less chance there is for the integrity of the inner primary coating to be broken, thereby leaving the remainder of the inner primary coating on the surface of the optical fiberglass.

The fiber pull-out friction test can be performed as follows. The sample consists of bare neat optical fibers, one end of which is embedded in a sheet of the cured inner primary coating to be tested. This assembly is called Rheometrics R
Mount in an appropriate device, such as an SA-II rheometer, and set the temperature to a typical ribbon strip temperature (eg, 90 ° C.).
And slowly pull the fibers from the sheet at a rate of 0.1 mm / sec. The device records and plots force versus distance. The plot typically shows a negative slope curve area, which results from a decrease in the contact area between the fiber and the coating as the fiber is withdrawn. The slope is measured and the result of the test. A small slope value corresponds to a low fiber pull-out friction, and a large value corresponds to a large friction. The test was performed on three test samples, and the average value was used as the final result of the test.

Crack Propagation The crack propagation test measures the cohesive strength of the inner primary coating. The greater the cohesive strength of the inner primary coating, the greater the amount of energy required to separate the inner primary coating. Therefore, the inner primary coating with high cohesive strength is
It is capable of withstanding greater stripping forces during stripping of the ribbon, with less breakaway separation and less residue on the surface of the optical glass fiber than the inner primary coating with lower cohesive strength.

The crack propagation can be measured as follows. First, a 0.075 mm thick film is drawn from the internal primary composition. The film was then placed in a nitrogen atmosphere under a 1.0 D
Curs when exposed to UV at J / cm ² . Length 35
Cut out three test zones of size mm, width 12 mm, and thickness 0.075 mm. A 2.5 mm length cut was made beside each band. Attach the band to the RSA-II rheometer, bring the temperature to 90 ° C. (typical ribbon stripping temperature) and apply a constant draw rate of 0.1 mm / sec to the test band. The measure of cohesive strength is the increase in length ΔL before the crack propagates across the width of the test zone. The gauge length is 23.
It is constant at 2 mm. The reported value is currently the average of three measurements.

Water Exfoliation The water absorption exfoliation test measures the resistance of a coating to exfoliation under high humidity conditions. Subtract from each internal primary coating composition to make a 3.0 mil film of that internal primary coating composition on a microscope slide, then Fusion D lamp, 120 W / cm, in a nitrogen atmosphere.
Cured by exposure to 1.0 J / cm ² of UV from Next, each outer primary coating was made by drawing the outer primary coating composition over the cured 3.0 mil inner primary film to form a 3.0 mil film, and forming it in the same manner as the inner primary coating. Cured.

The deionized water was placed in a 500 ml beaker and the coated microscope slide was immersed in the water.
The beaker with the coated slide was then placed in a 60 ° C. hot water bath. Observe for delamination every 15 minutes during the first hour, then every hour for up to 8 hours, then 24
Exfoliation was observed at time intervals until exfoliation was observed. The time recorded is the time at which it was determined that one half of the coating had detached from the glass substrate. Delamination generally starts at the exposed end of the sample and propagates into the interior. Since the coated fiber has no exposed ends, comparing the relative times at which one-half of the sample coating would release would be a more accurate approximation of the relative release rate that occurs for glass fibers. . For example, for each sample where the reported peel was greater than 24 hours, the 剥離 peel occurred at some point between 24-48 hours. Since the test was stopped after 72 hours, the sample reported as having a 剥離 peel of greater than 72 hours was one that had not reached that degree of peel at the end of the test.

Dry Adhesion and Wet Adhesion The adhesion of the cured sample to the glass plate at 50% relative humidity (dry adhesion) and 95% relative humidity (wet adhesion) was tested using a universal tester, Instron TTD. . The load cell had a capacity of 10 pounds.

A 20 × 20 cm polished glass plate (Alletch Associates catalog no. 26080) was used. Apply the test material to the glass plate,
Cured using a UV processor. The thickness of the cured film was about 75μ.

The cured films were maintained at about 23 ° C. and 50% relative humidity for 7 days before testing. Prior to removing the boards from the environmental chamber, a layer of slurry (milled polyethylene and water) was applied to the surface of the film to maintain moisture.

A test piece having a width of about 1 inch and a length of about 5 inch was cut in parallel with the tensile direction when the cured film was drawn. A thin layer of talc was applied to the first and third strips of each tensile film to reduce blocking during the adhesion test.

The equipment was corrected before testing. The speed of the crosshead was set at 10.00 in / min. The force required to remove four specimens from the glass plate for each material was measured and recorded on a strip chart recorder. The reported value is the average of four values of force measured in g.

Next, the test piece remaining on the glass plate was
It was kept in the environment room for an additional day at 3 ° C. and 95% relative humidity. Prior to removal of the board from the environmental chamber, a layer of slurry (milled polyethylene and water) was applied to the surface of the film to maintain moisture. For each material, 4
The force to remove the test pieces was measured as described above.

Discussion of Test Results By comparing Comparative Example A and Comparative Example B in Table 1, 2
% Ethoxylated dimethylsiloxane DC193 results in a dramatic reduction in fiber friction, thereby improving ribbon strippability, as reported in US Pat. No. 4,472,021. It can be seen that it improves. However, this improvement in ribbon strippability is only achieved with a substantial reduction in dry and wet adhesion and a reduction in the water strip test from more than 24 hours to only 30 minutes.

It can be seen from Examples 1 to 4 that the addition of non-reactive polyphenylalkylsiloxanes in place of the conventionally used ethoxylated dimethylsiloxanes completely unexpectedly restores resistance to water stripping or significantly further Improved ribbon strippability, as evidenced by improved and substantially restored dry and wet adhesion as compared to the comparative example, and of course reduced fiber friction as compared to comparative example A. You can see that there is.

While the invention has been described in detail with respect to particular embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made to the claimed invention without departing from its spirit and scope.

[0105]

[Table 1]

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Claims (22)

[Claims] 1. A liquid radiation-curable coating composition used to provide an internal primary optical fiberglass coating upon curing, the radiation-curable having a polymer backbone and at least one radiation-curable functional group as premix components. After curing, comprising: (a) a fiber pull-out friction of about 18 or less, (b) a water soak release time of greater than 24 hours to 1/2 release, and (C) a coating composition having a combination of properties of wet and dry adhesion, greater than 10 g force. 2. The premix component further comprises at least one organofunctional silane adhesion promoter.
3. The coating composition according to item 1. 3. The coating composition according to claim 1, wherein the water immersion peel time is longer than 48 hours until 1/2 peel. 4. The coating composition according to claim 1, wherein the water immersion peel time is longer than 72 hours until 1/2 peel. 5. The coating composition according to claim 1, wherein the fiber pull-out friction is about 12 or less. 6. The coating composition of claim 5, wherein the water immersion peel time is greater than 72 hours to 1/2 peel. 7. A coated optical glass fiber having an optical glass fiber core and a cured internal primary coating on the core, the radiation having a polymer backbone and at least one radiation-curable functional group as premix components. Curable oligomer,
And a non-reactive polyphenylalkylsiloxane
After curing, properties of (a) fiber pull-out friction of about 18 or less, (b) water immersion peel time of more than 24 hours to 1/2 peel, and (c) wet and dry adhesion of greater than 10 g force. A coated optical glass fiber having the cured inner primary coating and the core formed by applying and curing a liquid radiation curable coating composition having the combination to the glass fiber. 8. The premix component further comprising at least one organofunctional silane adhesion promoter.
A coated optical glass fiber according to claim 1. 9. A liquid radiation curable coating composition used to provide an internal primary optical glass fiber coating upon curing, wherein the premix component comprises: (A) a polymer backbone and at least one radiation curable functional group. A radiation curable oligomer having: (B) an organofunctional silane adhesion promoter; and (C) a non-reactive polyphenylalkylsiloxane, wherein the components comprise: Efficient to have a combination of the following properties: a fiber pull-out friction of 18 or less, (b) a water soak release time of greater than 24 hours to 1/2 release, and (c) wet and dry adhesion of greater than 10 g force. Coating composition present in an amount. 10. The coating composition according to claim 9, further comprising at least one reactive diluent. 11. The coating composition according to claim 9, further comprising at least one photoinitiator. 12. A liquid radiation curable coating composition used to provide an internal primary optical fiberglass coating upon curing, wherein the premix component comprises: (A) a polymer backbone and at least one attached to the polymer backbone. At least one radiation-curable oligomer having one radiation-curable functional group; (B) optionally at least one organofunctional silane adhesion promoter; and (C) an effective amount of at least one non-reactive. A coating composition comprising a reactive polyphenylalkylsiloxane, (D) optionally at least one reactive diluent, and (E) optionally an effective amount of at least one photoinitiator. 13. A liquid radiation curable coating composition used to provide an internal primary optical glass fiber coating upon curing, wherein the premix component comprises: (A) a polymer backbone and at least one attached to the polymer backbone. At least one radiation-curable oligomer having one radiation-curable functional group; (B) at least one organofunctional silane adhesion promoter; (C) an effective amount of at least one non-reactive polyphenylalkyl. A coating composition comprising a siloxane, (D) optionally at least one reactive diluent, and (E) optionally an effective amount of at least one photoinitiator. 14. A liquid radiation-curable coating composition used to provide an internal primary optical fiberglass coating upon curing, wherein the premix component comprises: (A) a polymer backbone and at least one attached to the polymer backbone. At least one radiation-curable oligomer having one radiation-curable functional group; (B) at least one organofunctional silane adhesion promoter; (C) an effective amount of at least one non-reactive polyphenylalkyl. A coating composition comprising a siloxane, (D) at least one reactive diluent, and (E) optionally an effective amount of at least one photoinitiator. 15. The liquid radiation-curable coating composition used to provide an internal primary optical fiberglass coating upon curing, wherein the premix component comprises: (A) at least one of from about 10% to about 90% by weight; Radiation-curable urethane (meth) acrylate oligomers having an oligomer backbone, at least one urethane linking group, and at least one radiation-curable end-capping group; (B) at least one organofunctional silane bond (C) from about 0.1% to about 30% by weight of at least one non-reactive polyphenylalkylsiloxane; (D) from about 10% to about 90% by weight of at least one reactive dilution. A coating composition comprising an agent, and (E) optionally an effective amount of at least one photoinitiator. 16. The non-reactive polyphenylalkylsiloxane has the formula (I): (In the formula, each R is independently a linear or branched chain (having 1 to 1 carbon atoms)
2) represents an alkyl or phenyl group, where n is greater than 1, wherein the mole percent of phenyl is at least about 10 mole percent. The coating composition according to any one of claims 12 to 15, which has a siloxane repeating unit having the general structure of (1). 17. The non-reactive polyphenylalkylsiloxane has the formula (II): (In the formula, each R is independently a linear or branched chain (having 1 to 1 carbon atoms)
2) represents an alkyl group or a phenyl group, n is 1 or more, and X and Y independently represent a non-reactive group, provided that the average mole percent of phenyl is at least about 10 mole percent. The coating composition according to any one of claims 12 to 15, which has the general structure of (12). 18. X and Y independently represent a non-reactive group selected from straight or branched chain alkyl, cycloalkyl or aryl groups having 1 to 12 carbon atoms.
A coating composition according to claim 17. 19. The coating composition according to claim 16, wherein R is a group selected from the group consisting of methyl, ethyl, and propyl when R is an alkyl group having 1 to 12 carbon atoms. 20. The method of claim 20, wherein the mole percent of phenyl is at least about 20.
The coating composition according to claim 16 or 17, which is mol%. 21. The coating composition of claim 16, wherein the mole percent of phenyl is in the range of about 20 to 60 mole percent. 22. A premix component comprising: (A) at least one radiation curable urethane (meth) acrylate oligomer having an oligomer backbone, at least one urethane linking group, and at least one radiation curable endcapping group; And (B) a radiation-curable internal primary on the optical glass fiber formed by applying and curing a liquid radiation-curable coating composition comprising at least one organofunctional silane adhesion promoter on the optical glass fiber. In a method for improving the balance between ribbon strippability and wet adhesion of a coating, prior to application and curing, the liquid coating composition comprises: (C) at least one of from about 0.1% to about 30% by weight; An improved process comprising the addition of a non-reactive polyphenylalkylsiloxane of any type.