KAMO SATOSHI (JP)
KUROSAWA TAKAHIKO (JP)
JSR CORP (JP)
YAMAGUCHI HIROSHI (JP)
KAMO SATOSHI (JP)
KUROSAWA TAKAHIKO (JP)
| WO2002074849A2 | 2002-09-26 | |||
| WO2005026228A1 | 2005-03-24 | |||
| WO2006025733A1 | 2006-03-09 |
| US20050256287A1 | 2005-11-17 | |||
| US20030119934A1 | 2003-06-26 | |||
| EP1070682A1 | 2001-01-24 |
Claims
1. A radiation curable liquid resin composition comprising: (A) a urethane (me th) aery late having a structure derived from polypropylene glycol with a number average molecular weight of from about 500 to about 4,000; (B) a urethane (me th) aery late having a bisphenol structure; and (C) a compound having one ethylenically unsaturated group, Wherein component (C) comprises isobornyl (meth)acrylate in an amount of from about 40 to about 80 mass% of the total 100 mass% of the component (C).
2. The radiation curable liquid resin composition according to claim 1, wherein the component (C) further comprises N-vinylcaprolactam.
3. The radiation curable liquid resin composition according to claim 1 or 2, wherein the component (C) comprises isobornyl (meth) aery late and N- vinylcaprolactam in an amount of from about 75 to about 100 mass% in 100 mass% of the compound having one ethylenically unsaturated group.
4. The radiation curable liquid resin composition according to any of claims 1 to 3, which is used as a material of optical fiber ribbons.
5. An optical fiber coating layer obtained by curing the radiation curable liquid resin composition according to any one of claims 1 to 3.
6. An optical fiber ribbon having the coating layer according to claim 5.
7. A process to coat one or more optical fibers with the radiation curable liquid resin composition of Claim 1, comprising: a) providing one or more optical fibers coated with one or more curable liquid resin compositions; b) applying radiation to cure the liquid resin compositions on the one or more optical fibers; c) arranging one or more optical fibers from step b) in a desired configuration; d) applying the radiation curable liquid resin composition of claim 1 to the one or more optical fibers in the desired configuration of step c); e) applying radiation to cure the radiation curable liquid resin composition of Claim 1. |
Title: Ribbon matrix material for optical fiber with excellent bending resistance
FIELD OF THE INVENTION
The present invention relates to a curable liquid resin composition suitable as a material for optical fiber ribbons.
BACKGROUND OF THE INVENTION
In the manufacture of optical fibers, a glass fiber is produced by spinning molten glass, and a resin coating is provided over the glass fiber for protection and reinforcement. This step is referred to as fiber drawing. As the resin coating, a structure is known in which a flexible primary coating layer is formed on the surface of an optical fiber and a rigid secondary coating layer is applied over the primary coating layer. A structure is also known in which the resin-coated optical fibers are placed side by side in a plane and bundled with a bundling material to produce a ribbon-shaped coating layer for practical use. A resin composition for forming the primary coating layer is called a primary material, a resin composition for forming the secondary coating layer is called a secondary material, and a resin composition for forming the ribbon-shaped coating layer is called a ribbon matrix material (see JP-A-2005-255955 and JP- A-2006-036989).
Since the optical fiber covered with a ribbon matrix material is frequently bent when the optical fiber is attached to a connector, the ribbon matrix material must not fracture during the attachment work or the like. That is, the ribbon matrix material must have excellent bending resistance.
SUMMARY OF THE INVENTION The first aspect of the instant claimed invention is a radiation curable liquid resin composition comprising:
(A) a urethane (me th) aery late having a structure derived from polypropylene glycol with a number average molecular weight of from about 500 to about 4,000;
(B) a urethane (meth)acrylate having a bisphenol structure; and (C) a compound having one ethylenically unsaturated group,
Wherein component (C) comprises isobornyl (me th) aery late in an amount of from about 40 to about 80 mass% of the total 100 mass% of the component (C) and optionally further comprises N-vinylcaprolactam.
The second aspect of the instant claimed invention is an optical fiber coating layer obtained by curing the radiation curable liquid resin composition of the first aspect of the instant claimed invention.
The third aspect of the instant claimed invention is an optical fiber ribbon having a cured coating layer of the first aspect of the instant claimed invention. The fourth aspect of the instant claimed invention is a process to coat one or more optical fibers with the radiation curable liquid resin composition of the first aspect of the instant claimed invention, comprising: a) providing one or more optical fibers coated with one or more curable liquid resin compositions; b) applying radiation to cure the liquid resin compositions on the one or more optical fibers; c) arranging one or more optical fibers from step b) in a desired configuration; d) applying the radiation curable liquid resin composition of the first aspect of the instant claimed invention to the one or more optical fibers in the desired configuration of step c); e) applying radiation to cure the radiation curable liquid resin composition of the first aspect of the instant claimed invention.
An objective of the present invention is to provide a radiation curable liquid resin composition suitable for use as an optical fiber ribbon matrix
material which has very high Young's modulus of elasticity and excellent bending resistance.
The inventors of the present invention have prepared urethane (me th)acrylate -containing curable liquid resin compositions using various components, and have evaluated the strength, functions, and bending resistance of the cured product as the optical-fiber coating layers. As a result, the inventors have found that the above object can be achieved by using a urethane (meth)acrylate having a structure derived from polypropylene glycol, a urethane (meth)acrylate having a bisphenol structure, and a compound having one specific ethylenically unsaturated group in combination.
The coating obtained from the curable liquid resin composition of the present invention has very high Young's modulus of elasticity and excellent bending resistance, and is suitably used as a material of optical fiber ribbons.
DETAILED DESCRIPTION OF THE INVENTION
The urethane (me th) aery late used as the component (A) of the present invention is produced by reacting a polypropylene glycol (polyol) having a number average molecular weight of from about 500 to about 4,000, a diisocyanate, and a hydroxyl group -containing (meth)acrylate, for example. Specifically, the urethane (meth) aery late is produced by reacting isocyanate groups of the diisocyanate with hydroxyl groups of the polyol and the hydroxyl group -containing (meth)acrylate.
As the method for reacting these compounds, a method of reacting the polyol, the diisocyanate, and the hydroxyl group-containing (meth) aery late all together; a method of reacting the polyol with the diisocyanate, and reacting the resulting product with the hydroxyl group -containing (meth) aery late; a method of reacting the diisocyanate with the hydroxyl group -containing (meth)acrylate, and reacting the resulting product with the polyol; a method of reacting the diisocyanate with the hydroxyl group-containing (meth) aery late, reacting the resulting product with the polyol, and further reacting the
resulting product with the hydroxyl group -containing (meth)acrylate; and the like can be given.
The polyol used is a polypropylene glycol having a number average molecular weight of from about 500 to about 4,000. The number average molecular weight is determined by gel permeation chromatography (GPC method) as a polystyrene -reduced molecular weight.
The polypropylene glycol is commercially available as "PPG-400", "PPGlOOO", "PPG2000", "PPG3000", "EXCENOL 720", "EXCENOL 1020", and . "EXCENOL 2020" (manufactured by Asahi Glass Urethane Co., Ltd.), and the like.
As examples of the diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5- naphthalene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate, 4,4'- diphenylmethane diisocyanate, 3,3'-dimethylphenylene diisocyanate, 4,4'- biphenylene diisocyanate, 1,6-hexane diisocyanate, isophorone diisocyanate, methylenebis(4-cyclohexylisocyanate), 2,2,4-trimethylhexamethylene diisocyanate, bis(2-isocyanateethyl)fumarate, 6-isopropyl-l,3-phenyl diisocyanate, 4-diphenylpropane diisocyanate, lysine diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, tetramethylxylylene diisocyanate, 2,5(or 2,6)- bis(isocyanatemethyl)-bicyclo[2.2.1]heptane, and the like can be given. Of these, 2,4-tolyiene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, and methylenebis(4-cyclohexylisocyanate) are preferable. These diisocyanates may be used either individually or in combination of two or more.
Examples of (meth)acrylates containing a hydroxyl group include 2- hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth) aery late, 2-hydroxy-3-phenyloxypropyl (meth)acrylate, 1,4-butanepolyol mono (meth) aery late, 2-hydroxyalkyl(meth)acryloyl phosphate, 4-
hydroxycyclohexyl (meth)acrylate, 1,6-hexanepolyol mono(meth)acrylate, neopentyl glycol mono(meth)acrylate, trimethylolpropane di(meth)acrylate, trimethylolethane di(meth)acrylate, pentaerythritol tri(meth) aery late, dipentaerythritol penta(meth)acrylate, and (meth)acrylates shown by the following formulas (1) and (2):
CH 2 =C(R 1 )- COOCH 2 CH 2 - (OCOCH 2 CH 2 CH 2 CH 2 CH 2 )J-OH (1)
CH 2 =C(R 1 )- COOCH 2 CH(OH)CH 2 -O- ff \ (2)
wherein R 1 represents a hydrogen atom or a methyl group and n is an integer from 1 to 15.
A compound obtained by the addition reaction of (me th) acrylic acid and a glycidyl group-containing compound such as an alkyl glycidyl ether, allyl glycidyl ether, or glycidyl (meth)acrylate may also be used. Of these hydroxyl group -containing (meth)acrylates, 2 -hydroxy ethyl (meth)acrylate and 2- hydroxypropyl (meth)acrylate are preferable.
These hydroxyl group -containing (meth) aery late compounds may be used either individually or in combination of two or more.
The polyol, the diisocyanate, and the hydroxyl group -containing (meth)acrylate are preferably used so that the isocyanate groups included in the diisocyanate and the hydroxyl groups included in the hydroxyl group - containing (meth) aery late are respectively from about 1.1 to about 3 equivalents and from about 0.2 to about 1.5 equivalents for one equivalent of the hydroxyl groups included in the polyol.
When reacting these compounds, it is preferable to use a urethanization catalyst such as copper naphthenate, cobalt naphthenate, zinc naphthenate, dibutyltin dilaurate, triethylamine, l,4-diazabicyclo[2.2.2]octane, or 2,6,7- trimethyl-l,4-diazabicyclo[2.2.2]octane in an amount of 0.01 to 1 part by mass
for 100 parts by mass of the reactants. The reaction temperature is preferably from about 10 to about 9O 0 C, and particularly preferably from about 30 to about 8O 0 C.
The hydroxyl group -containing (meth)acrylate may be partially replaced with a compound having a functional group which can be added to an isocyanate group. As examples of such compound, y- mercaptotrimethoxysilane, γ-aminotrimethoxysilane, or the like can be given. Use of these compounds improves adhesion to a substrate such as glass.
The urethane (meth)acrylate used as the component (A) is added to the curable liquid resin composition in an amount of preferably from about 10 to about 50 mass%, more preferably from about 20 to about 40 mass%, and particularly preferably from about 25 to about 35 mass% in order to ensure bending resistance of the cured product.
The urethane (meth)acrylate used as the component (B) of the present invention has a bisphenol structure and is produced by, for example, reacting a polyol having a bisphenol structure, a poly isocyanate, and a (me th) aery late containing a hydroxyl group. Specifically, the urethane (me th) aery late is produced by reacting isocyanate groups of the diisocyanate with hydroxyl groups of the polyol and the hydroxyl group -containing (meth)acrylate. This reaction can be carried out in the same manner as the reaction for producing the urethane (meth)acrylate of the component (A), except for using a polyol having a bisphenol structure instead of polypropylene glycol.
As examples of the polyol having a bisphenol structure, an alkylene oxide addition polyol of bisphenol A, an alkylene oxide addition polyol of bisphenol F, hydrogenated bisphenol A, hydrogenated bisphenol F, an alkylene oxide addition polyol of hydrogenated bisphenol A, alkylene oxide addition polyol of hydrogenated bisphenol F, and can be given. Of these, a polyol having a bisphenol structure, particularly an alkylene oxide addition polyol of bisphenol A is preferable. These polyols are commercially available as "Uniol
DA400", "Uniol DA7Q0", "Uniol DAlOOO", and "Uniol DB400" (manufactured by Nippon Oil and Fats Co., Ltd.), and the like.
The content of the urethane (me th) aery late having a bisphenol structure of the component (B) in the curable liquid resin composition is preferably from about 10 to about 40 mass%, more preferably from about 20 to about 30 mass%, and particularly from about 20 to about 30 mass%, in order to maintain high Young's modulus of elasticity and ensure bending resistance of the cured product.
In addition to the urethane (meth)acrylate (A) and urethane (me th) aery late (B), other urethane (meth)acrylates (urethane (me th) aery late (B')) may optionally be added to the curable liquid resin composition of the present invention to the extent not impairing the effect of the present invention. Although not specifically limited, a urethane (meth) aery late which does not contain a polyol component and is obtained by reacting a diisocyanate compound and a hydroxyl group-containing (meth) aery late compound can be given as an example of the urethane (meth) aery late (B'). As more specific examples of the urethane (meth)acrylate (B'), a urethane (meth)acrylate having a structure in which hydroxy ethyl (meth) aery late s are bonded to both ends of 2,4-tolylene diisocyanate, an equimolar reaction product of 2,4-tolylene diisocyanate, hydroxyethyl (meth) aery late, and hydroxypropyl (meth) aery late, and the like can be given.
The component (B'), that is, urethane (meth)acrylates other than the component (A) and the component (B), is added to the curable liquid resin composition in an amount preferably of from about 0 to about 30 mass%, more preferably from about 10 to about 25 mass%, and particularly preferably from about 15 to about 25 mass%.
As examples of the compound having one ethylenically unsaturated group (monofunctional monomer) of component (C), vinyl group -containing lactams such as N-vinylpyrrolidone and N-vinylcaprolactam, alicyclic structure-containing (meth)acrylates such as isobornyl (meth)acrylate, bornyl
(meth)acrylate, tricyclodecanyl (meth)acrylate, and dicyclopentanyl (meth)acrylate, benzyl (meth)acrylate, 4-butylcyclohexyl (meth)acrylate, acryloylmorpholine, vinylimidazole, vinylpyridine, and the like can be given. Further examples include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (me th) aery late, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (me th) aery late, amyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (me th) aery late, heptyl (me th) aery late, octyl (meth) aery late, isooctyl (meth)acrylate, 2-ethylhexyl (meth) aery late, nonyl (meth)acrylate, decyl (meth) aery late, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth) aery late, lauryl (meth) aery late, stearyl (meth)acrylate, isostearyl (meth) aery late, tetrahydrofurfuryl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethylene glycol (meth) aery late, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, methoxyethylene glycol (meth) aery late, ethoxyethyl (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, diacetone (meth)acrylamide, isobutoxymethyl (meth) aery lamide, N,N-dimethyl (meth)acrylamide, t-octyl (meth) aery lamide, dimethylaminoethyl (meth) aery late, diethylaminoethyl (meth) aery late, 7-amino-3,7-dimethyloctyl (meth) aery late, N,N-diethyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, hydroxybutyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether, 2-ethylhexyl vinyl ether, and compounds shown by the following formulas (3) to (6).
CH 2 =C(R 2 )- CO— (R 3 O) r — R 4 (3) O
wherein R 2 represents a hydrogen atom or a methyl group, R 3 represents an alkylene group having 2 to 6, and preferably 2 to 4 carbon atoms, R 4 represents a hydrogen atom or an alkyl group having 1 to 12, and preferably 1 to 9 carbon atoms, and r represents an integer from 0 to 12, and preferably from 1 to 8.
wherein R 5 represents a hydrogen atom or a methyl group, R 6 represents an alkylene group having 2 to 8, and preferably 2 to 5 carbon atoms, R 7 represents a hydrogen atom or a methyl group, and p represents an integer preferably from 1 to 4.
wherein R 8 , R 9 , R 10 , and R 11 individually represent H or CH3, and q represents an integer from 1 to 5.
Of these compounds having one ethylenically unsaturated group, N- vinylpyrrolidone, vinyl group -containing lactam such as N-vinylcaprolactam, isobornyl (meth)acrylate, and lauryl acrylate are preferable. As commercially available products of these compounds having one ethylenically unsaturated group, "IBXA" (manufactured by Osaka Organic Chemical Industry Co., Ltd.), "Aronix M-Hl", "Aronix M-113", "Aronix M-114",
"Aronix M-117", and "Aronix TO-1210" (manufactured by Toagosei Co., Ltd.) may be given.
The content of the compound having one ethylenically unsaturated group of the component (C) in the curable liquid resin composition is preferably from about 15 to about 45 mass%, more preferably from about 20 to about 40 mass%, and particularly preferably from about 25 to about 35 mass%, in order to maintain high Young's modulus of elasticity and ensure bending resistance of the cured product.
In the present invention, from about 40 to about 80 mass%, and preferably from about 50 to about 70 mass% of the compounds having one ethylenically unsaturated group of the component (C) is isobornyl
(me th) aery late.
A combined use of isobornyl (meth)acrylate and N-vinylcaprolactam as the component (C), preferably in an amount of from about 75 to about 100 mass%, and particularly preferably from about 75 to about 90 mass%, in the compounds having one ethylenically unsaturated group is preferable in order to maintain high Young's modulus of elasticity and ensure bending resistance of the cured product.
To the extent not impairing the effect of the present invention, a compound having two or more ethylenically unsaturated groups (a polyfunctional monomer) other than the component (A) may be added to the liquid curable resin composition of the present invention as a component (D).
As specific examples of the compound having two or more ethylenically unsaturated groups , trimethylolpropane tri(meth)acrylate, trimethylolpropanetrioxyethyl (me th) aery late, pentaerythritol tri(meth)acrylate, ethylene glycol di(meth)acrylate, triethylene glycol diacrylate, tetraethylene glycol di(meth) aery late, bis(meth)(acryloyloxymethyl)tricyclo[5.2.1.0 2 ' 6 ]decane (also called
"tricyclodecanediyldimethanol di(meth)acrylate"), polyethylene glycol di(meth) aery late, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol
di(meth) aery late, neopentyl glycol di(meth) aery late, tripropylene glycol di(meth) aery late, neopentyl glycol di(meth)acrylate, both terminal (meth) acrylic acid addition compound of bisphenol A diglycidyl ether, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, polyester di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tris(2-hydroxyethyl)isocyanurate di(meth)acrylate, tricyclodecanedimethanol di(meth) aery late, di(meth)acrylate of ethylene oxide or propylene oxide addition diol of bisphenol A, di(meth)acrylate of ethylene oxide or propylene oxide addition diol of hydrogenated bisphenol A, epoxy(meth)acrylate in which (meth)acrylate is added to diglycidyl ether of bisphenol A, triethylene glycol divinyl ether, and the like can be given.
As commercially available products of these polymerizable polyfunctional monomers (D), "NK-Ester A-DCP" and "Yupimer UV" (manufactured by Shin-Nakamura Chemical Co., Ltd.), "SA- 1002" (manufactured by Mitsubishi Chemical Corp.), "Aronix M-215", "Aronix M- 315", "Aronix M-325", and "Aronix TO-1210" (manufactured by Toagosei Co., Ltd.), and the like can be given.
These polymerizable polyfunctional monomers of component (D) are used in the curable liquid resin composition of the present invention in an amount of preferably from about 0 to about 5 mass%, and particularly preferably from about 0 to about 3 mass%. If more than about 5 mass%, bending resistance of the cured products may decrease.
The curable liquid resin composition of the present invention may further contain a polymerization initiator (E). As the polymerization initiator, a heat polymerization initiator or a photoinitiator may be used.
When the curable liquid resin composition of the present invention is heat curable, a heat polymerization initiator such as a peroxide or azo compound is usually used. As specific examples of the heat polymerization initiator, benzoyl peroxide, t-butyl-oxybenzoate, azobisisobutyronitrile, and the like can be given.
A photoinitiator is used when the curable liquid resin composition of the present invention is photo-curable. It is preferable to use a photosensitizer in combination, if required. As examples of the photoinitiator, 1- hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, 4,4'- dimethoxybenzophenone, 4,4'-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, l-(4-isopropylphenyl)- 2-hydroxy-2-methylpropane-l-one, 2-hydroxy-2-methyl-l-phenylpropane-l-one, thioxanethone, diethylthioxanthone, 2-isopropylthioxanthone, 2- chlorothioxanthone, 2-methyl-l-[4-(methylthio)phenyl]-2-morpholino-propane- 1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis-(2,6- dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide; "IRGACURE 184", "IRGACURE 369", "IRGACURE 651", "IRGACURE 500", "IRGACURE 907", "CGI 1700", "CGI 1750", "CGI 1850", "CG24-61", "Darocur 1116", and
"Darocure 1173" (manufactured by Ciba Specialty Chemicals Co.); "Lucirin TPO" (manufactured by BASF); "Ubecryl P36" (manufactured by UCB); and the like can be given.
As examples of the photosensitizer, trie thy 1 amine, diethylamine, N- methyldiethanolamine, ethanolamine, 4-dimethylaminobenzoic acid, methyl 4- dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, isoamyl 4- dimethylaminobenzoate; "Ubecryl P102", "Ubecryl P103", "Ubecryl P104", and "Ubecryl P 105" (manufactured by UCB); and the like can be given.
When curing the curable liquid resin composition of the present invention using heat and ultraviolet rays, the heat polymerization initiator and the photoinitiator can be used in combination. The content of the polymerization initiator (E) in the composition is preferably from about 0.1 to about 10 mass%, and particularly preferably from about 0.3 to about 7 mass%. Various additives such as antioxidants, coloring agents, UV absorbers, light stabilizers, silane coupling agents, heat polymerization inhibitors,
leveling agents, surfactants, preservatives, plasticizers, lubricants, solvents, fillers, aging preventives, wettability improvers, and coating surface improvers may be optionally added to the curable liquid resin composition of the present invention insofar as the characteristics of the present invention are not adversely affected.
A cured film obtained by curing the curable liquid resin composition preferably has Young's modulus of elasticity of from about 700 to about 1,200 MPa.
An aspect of the instant claimed invention is a process to coat one or more optical fibers with the radiation curable liquid resin composition of the first aspect of the instant claimed invention, comprising: a) providing one or more optical fibers coated with one or more curable liquid resin compositions; b) applying radiation to cure the liquid resin compositions on the one or more optical fibers; c) arranging one or more optical fibers from step b) in a desired configuration; d) applying the radiation curable liquid resin composition of the first aspect of the instant claimed invention to the one or more optical fibers in the desired configuration of step c); e) applying radiation to cure the radiation curable liquid resin composition of the first aspect of the instant claimed invention.
It is known in the art how to manufacture optical fibers and coat them with one or more radiation curable liquid resin compositions. The one or more radiation curable liquid resin compositions may include a Primary Coating, a Secondary Coating and an Ink Coating. Primary Coatings, Secondary Coatings and Ink Coatings for optical fiber are commercially available from JSR Corporation in Japan, http://www.jsr.co.ip/isr e/
and are also commercially available from DSM Desotech in the United States, http://www.dsm.com/en US/html/dsmd/desotech home.htm and other countries.
The arrangement of optical fibers into a ribbon configuration is standardized based on either industry standard or government standard or both depending upon where the optical fiber is manufactured and used. People of ordinary skill in the art of optical fibers know what type of ribbon configurations are acceptable in what jurisdiction.
The composition of the present invention may be cured by applying heat or radiation. It is preferable under most circumstances to cure by applying radiation. Radiation used herein refers to infrared rays, visible light, ultraviolet rays, X-rays, electron beams, α-rays, β-rays, γ-rays, and the like.
The product of the process is typically referred to as an "optical fiber ribbon" which is one or more optical fibers arranged in a ribbon configuration wherein the composition of the instant claimed invention is used as the Matrix material for that ribbon configuration.
The present invention will be described in more detail by way of examples, which should not be construed as limiting the present invention.
EXAMPLES
Preparation Example 1: synthesis of urethane (meth)acrylate (A)
A reaction vessel equipped with a stirrer was charged with 77.4 g of polypropylene glycol having a number average molecular weight of 2,000, 13.5 g of 2,4-tolylene diisocyanate, 0.02 g of 2,6-di-t-butyl-p-cresol. After cooling the mixture to 15 0 C while stirring, 0.08 g of dibutyltin dilaurate was added. The mixture was reacted for one hour while stirring and controlling the temperature at 45 0 C or less. After the addition of 9.0 g of 2-hydroxyethyl acrylate dropwise, the mixture was allowed to react at about 6O 0 C with stirring. The reaction was terminated when the residual isocyanate was 0.1 wt% or less to obtain a polyether urethane acrylate having a number average
molecular weight of 2,580. This polyether ure thane acrylate is referred to as (UA-I).
Preparation Example 2: synthesis of urethane (meth) acrylate (B) A reaction vessel equipped with a stirrer was charged with 40.8 g of polyoxyethylene bisphenol A ether having a number average molecular weight of 400, 35.5 g of 2,4-tolylene diisocyanate, 0.02 g of 2,6-di-t-butyl-p-cresol. After cooling the mixture to 15 0 C while stirring, 0.08 g of dibutyltin dilaurate was added. The mixture was reacted for one hour while stirring and controlling the temperature at 45 0 C or less. After the addition of 23.7 g of 2- hydroxyethyl acrylate dropwise, the mixture was allowed to react at about 6O 0 C with stirring. The reaction was terminated when the residual isocyanate was 0.1 wt% or less to obtain a polyether urethane acrylate having a number average molecular weight of 980. This polyether urethane acrylate is referred to as (UA-2).
Preparation Example 3: synthesis 1 of urethane (meth)acrylate (B')
A reaction vessel equipped with a stirrer was charged with 41.4 g of 2,4- tolylene diisocyanate, 0.02 g of 2,6-di-t-butyl-p-cresol, 0.08 g of dibutyltin dilaurate, and 0.008 g of phenothiazine. The mixture was cooled to 2O 0 C with stirring. After the addition of 27.6 g of 2-hydroxyethyl acrylate dropwise, the mixture was allowed to react for one hour while stirring and controlling the temperature at 25 0 C or lower. After further addition of 30.9 g of 2- hydroxypropyl acrylate, the mixture was reacted at about 6O 0 C with stirring. The reaction was terminated when the residual isocyanate concentration was 0.1 wt% or less to obtain a urethane acrylate not having a polyol structure. This urethane acrylate is referred to as (UA-3). Preparation Example 4: synthesis 2 of urethane (meth) acrylate (B')
A reaction vessel equipped with a stirrer was charged with 42.9 g of 2,4- tolylene diisocyanate, 0.02 g of 2,6-di-t-butyl-p-cresol, 0.08 g of dibutyltin
dilaurate, and 0.008 g of phenothiazine. The mixture was cooled to 20 0 C with stirring. After the addition of 57.1 g of 2-hydroxyethyl acrylate dropwise, the mixture was allowed to react for one hour at room temperature while stirring and controlling the temperature at 25 0 C or lower. The reaction was terminated when the residual isocyanate concentration (in the total amount of the mixture) was 0.1 wt% or less to obtain a ure thane acrylate not having a polyol structure. This urethane acrylate is referred to as (UA-4).
Example 1 A reaction vessel equipped with a stirrer was charged with 28.0 g of urethane acrylate (UA-I), 24.0 g of urethane acrylate (UA-2), 20.0 g of urethane acrylate (UA- 3), 17.O g of isobornyl acrylate, 9.0 g of N- vinylcaprolactam, 0.8 g of polymerization initiator "Lucirin TPO" (manufactured by BASF), and 0.3 g of an antioxidant "Irganox 245" (manufactured by Ciba Specialty Chemicals Co., Ltd.). The mixture was stirred at 5O 0 C until a homogeneous solution was obtained, thereby obtaining a curable liquid resin composition.
Example 2 and Comparative Examples 1 to 3
Curable liquid resin compositions of Example 2 and Comparative Examples 1 to 3 were prepared in the same manner as in Example 1 except for using the components shown in Table 1. The amounts of the components are shown by parts by mass in Table 1.
Test Examples The curable liquid resin compositions obtained in the above examples and comparative examples were cured using the following method to prepare specimens. The specimens were evaluated as follows. The results are shown in Table 1. 1. Young's modulus
The curable liquid resin composition was applied to a glass plate using an applicator bar with a gap size of 381 μm, and was cured by applying ultraviolet rays at a dose of 1 J/cm 2 in air to obtain a film for measuring the Young's modulus. The film was cut into a strip-shaped sample with a width of 6 mm and a length of 25 mm (portion to be pulled). The sample was subjected to a tensile test at a temperature of 23 0 C and a humidity of 50%. The Young's modulus was calculated from the tensile strength at a strain of 2.5% and a tensile rate of 1 mm/min. 2. Bending resistance A cured film with a thickness of 130 μm obtained at a dose of 300 mJ/cm 2 in air was cut into strips, each having a width of 1 cm to obtain test specimens. Bending resistance of the test specimen was measured by folding the test specimen using the MIT tester according to JIS P-8115 and counting the number of times of folding before the test specimen fractured. The test was carried out under the conditions of a load of 1.5 kg, a folding angle of
±135°, a curvature radius of a bending surface of 1.5 mm, and a folding rate of 87.5 folding/minute.
An average of ten test results for each test specimen was taken as the number of folding of that test specimen.
Table 1
In Table 1:
"NK-Ester A-DCP" : bis(meth)(acryloyloxymethyl)tricyclo[5.2.1.0 2 . 6 ]decane (also called tricyclodecanediyldimethanoldi(meth)acrylate) (manufactured by
Shin Nakamura Chemical Co., Ltd.)
"Lucirin TPO": 2,4,6-trimethylbenzoyldiphenylphosphine oxide (manufactured by Ciba Speciality Chemicals Co., Ltd.)
"Irgacure 907": 2-methyl-l-(4-methylthiophenyl)-2-morpholino-propane-l (manufactured by Ciba Specialty Chemicals Co., Ltd.)
"Irganoxl035": 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4- hydroxypbenyl)propionate] (manufactured by Ciba Specialty Chemicals Co.,
Ltd.)
"Irganox 245": ethylenebis(oxyethylene)bis[3-(5-tert-butyl-4-hydroxy-m- tolyl)propionate] (manufactured by Ciba Specialty Chemicals Co., Ltd.)
As clear from Table 1, the cured product obtained of the resin composition of the present invention has high Young's modulus of elasticity and excellent bending resistance.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. The use of the terms "a" and "an" and "the" and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non- claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-
described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.