U.S. patent application number 09/779732 was filed with the patent office on 2002-05-02 for forming size compositions, glass fibers coated with the same and fabrics woven from such coated fibers.
Invention is credited to Lammon-Hilinski, Kami, Lawton, Ernest L..
Application Number | 20020051882 09/779732 |
Document ID | / |
Family ID | 26879336 |
Filed Date | 2002-05-02 |
United States Patent
Application |
20020051882 |
Kind Code |
A1 |
Lawton, Ernest L. ; et
al. |
May 2, 2002 |
Forming size compositions, glass fibers coated with the same and
fabrics woven from such coated fibers
Abstract
The present invention provides coated fiber strand comprising at
least one fiber having a residue of an aqueous forming size
composition applied to at least a portion of a surface of the at
least one fiber, the aqueous forming size composition comprising:
(a) at least one starch; (b) at least one film-forming material;
(c) at least one lubricant; and (d) a plurality of discrete
particles that provide interstitial space between the at least one
fiber and at least one adjacent fiber sufficient to allow wet out
of the fiber strand. In one embodiment of the invention, the fibers
are glass fibers, the at least one starch comprises an oleophobic
starch, the at least one film-forming material comprises a N-vinyl
amide polymer, the at least one lubricant comprises an ester, and
the particles are dimensionally stable particles selected from
polymeric organic materials, non-polymeric organic materials,
polymeric inorganic materials, non-polymeric inorganic materials,
composite materials and mixtures thereof. In one non-limiting
embodiment of the invention, the particles comprise hexagonal boron
nitride particles and/or hollow particles formed from a copolymer
of styrene and acrylic monomer. The present invention also provides
a fabric incoporating the coated fabric strand and an electronic
support and an electronic circuit board incorporating the
fabric.
Inventors: |
Lawton, Ernest L.;
(Clemmons, NC) ; Lammon-Hilinski, Kami;
(Pittsburgh, PA) |
Correspondence
Address: |
PPG INDUSTRIES INC
INTELLECTUAL PROPERTY DEPT
ONE PPG PLACE
PITTSBURGH
PA
15272
US
|
Family ID: |
26879336 |
Appl. No.: |
09/779732 |
Filed: |
February 9, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60183605 |
Feb 18, 2000 |
|
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Current U.S.
Class: |
428/378 |
Current CPC
Class: |
H05K 1/0366 20130101;
H05K 2201/0209 20130101; C03C 25/255 20180101; C03C 25/26 20130101;
H05K 2201/0166 20130101; H05K 2201/0175 20130101; C03C 25/321
20130101; B05C 11/1039 20130101; Y10T 428/2938 20150115; H05K
2201/0245 20130101; B05C 11/1042 20130101; H05K 2201/0212 20130101;
H05K 2201/0254 20130101; H05K 2203/127 20130101; C03C 25/47
20180101; B05C 1/06 20130101 |
Class at
Publication: |
428/378 |
International
Class: |
D02G 003/00 |
Claims
Therefore, we claim:
1. A coated fiber strand comprising at least one fiber having a
residue of an aqueous forming size composition applied to at least
a portion of a surface of the at least one fiber, the aqueous
forming size composition comprising: (a) at least one starch; (b)
at least one film-forming material; (c) at least one lubricant; and
(d) a plurality of discrete particles that provide interstitial
space between the at least one fiber and at least one adjacent
fiber sufficient to allow wet out of the fiber strand.
2. The fiber strand according to claim 1, wherein the at least one
starch is present in the aqueous forming size composition in an
amount ranging from 10 to 90 weight percent on a total solids
basis.
3. The fiber strand according to claim 2, wherein the at least one
starch is an oleophobic starch.
4. The fiber strand according to claim 1, wherein the at least one
film forming material is present in the aqueous forming size
composition in an amount ranging from 0.1 to 30 weight percent on a
total solids basis.
5. The fiber strand according to claim 4, wherein the at least one
film forming material is selected from thermosetting materials and
thermoplastic materials.
6. The fiber strand according to claim 5, wherein the at least one
film forming material comprises a n-vinyl amide polymer.
7. The fiber strand according to claim 1, wherein the at least one
lubricant is present in the aqueous forming size composition in an
amount ranging from 5 to 50 weight percent of the aqueous forming
size composition on a total solids basis.
8. The fiber strand according to claim 7, wherein the at least one
lubricant comprises a highly crystalline wax having a polar
characteristic.
9. The fiber strand according to claim 7, wherein the at least one
lubricant is selected from cetyl palmitate, cetyl myristate, cetyl
laurate, octadecyl laurate, octadecyl myristate, octadecyl
palmitate, octadecyl stearate, trimethylolpropane tripelargonate,
natural spermaceti and triglyceride oils.
10. The fiber strand according to claim 8, wherein the forming size
composition further comprises at least one emulsifying agent
present in an amount ranging from 0.1 to 10 weight percent of the
forming size composition on a tolid solids basis; and at least one
cationic lubricant different from the at least one highly
crystalline wax present in an amount ranging from 0.01 to 15 weight
percent of the forming size composition on a total solids
basis.
11. The fiber strand according to claim 10, wherein the at least
one starch comprises an oleophobic starch; the at least one
film-forming material comprises a N-vinyl amide polymer; and the at
least one lubricant comprises an ester.
12. The fiber strand according to claim 1, wherein the at least one
fiber comprises at least one inorganic fiber comprising a glass
material selected from E-glass, D-glass, S-glass, Q-glass, E-glass
derivatives and combinations thereof.
13. The fiber strand according to claim 1, wherein the particles
are dimensionally stable selected from polymeric organic materials,
non-polymeric organic materials, polymeric inorganic materials,
non-polymeric inorganic materials, composite materials and mixtures
thereof.
14. The fiber strand according to claim 1, wherein the particles
are dimensionally stable.
15. The fiber strand according to claim 1, wherein the particles
are non-waxy particles.
16. The fiber strand according to claim 1, wherein the particles
have a Mohs' hardness value of no greater than that of the at least
one fiber.
17. The fiber strand according to claim 1, wherein the particles
are thermally conductive.
18. The fiber strand according to claim 1, wherein the particles
are electrically insulative.
19. The fiber strand according to claim 1, wherein the particles
have an average particle size ranging up to 1000 micrometers,
measured using laser scattering techniques.
20. The fiber strand according to claim 19, wherein the particles
have an average particle size ranging from 0.1 to 25 micrometers,
measured using laser scattering techniques.
21. The fiber strand according to claim 1, wherein the particles
are selected from polymeric organic materials, non-polymeric
organic materials, polymeric in organic materials, non-polymeric in
organic materials, composite materials and mixtures thereof.
22. The fiber strand according to claim 21, wherein the particles
comprise non-polymeric inorganic materials selected from graphite,
metals, oxides, carbides, nitrides, borides, sulfides, silicates,
carbonates, sulfates, hydroxides and mixtures thereof.
23. The fiber strand according to claim 22, wherein the particles
comprisehexagonal boron nitride.
24. The fiber strand according to claim 21, wherein the particles
comprise at least one organic polymeric material selected from
thermosetting polymeric materials and thermoplastic polymeric
materials.
25. The fiber strand according to claim 24, wherein the particles
comprise at least one thermoplastic polymeric material selected
from acrylic polymers, vinyl polymers, thermoplastic polyesters,
polyolefins, polyamides and thermoplastic polyurethanes.
26. The fiber strand according to claim 25, wherein the particles
compriseat least one acrylic copolymer of styrene and acrylic
monomer.
27. The fiber stand according to claim 24, wherein the particles
comprise at least one thermosetting polymeric material selected
from thermosetting polyesters, vinyl esters, epoxy materials,
phenolics, aminoplasts and thermosetting polyurethanes.
28. The fiber strand according to claim 1, wherein the particles
comprise at least one hollow particle.
29. The fiber strand according to claim 28, wherein the at least
one hollow particle comprises a copolymer of styrene and acrylic
monomer.
30. The fiber strand according to claim 1, wherein the particles
compriseboron nitride.
31. The fiber strand according to claim 1, wherein the particles
are first particles and the forming size composition further
comprises a plurality of additional discrete particles different
from the first particles.
32. The fiber strand according to claim 1, wherein the particles
comprise hexagonal boron nitride particles and acrylic copolymer
particles.
33. The fiber strand according to claim 1, wherein the particles
compriseat least one solid lubricant material.
34. The fiber strand according to claim 33, wherein the particles
compriseat least one inorganic solid lubricant material having a
lamellar structure.
35. The fiber strands according to claim 1, wherein the particles
have a lamellar structure.
36. The fiber strands according to claim 35, wherein the particles
are selected from boron nitride, graphite, metal dichalcogenides,
mica, talc, gypsum, kaolinite, calcite, cadmium iodide, silver
sulfide, and mixtures thereof.
37. The fiber strands according to claim 36, wherein the metal
dichalcogenide particles are selected from molybdenum disulfide,
molybdenum diselenide, tantalum disulfide, tantalum diselenide,
tungsten disulfide, tungsten diselenide, and mixtures thereof.
38. The fiber strand according to claim 1, wherein the particles
comprise at least one inorganic, non-hydratable material.
39. The fiber strand according to claim 1, wherein the particles
are selected from hydratable inorganic material, hydrated inorganic
material, and mixtures thereof.
40. The fiber strand according to claim 1, wherein the particles
are present in the forming size composition in an amount ranging
from 1 to 30 weight percent of the sizing composition on a total
solids basis.
41. The fiber strand according to claim 40, wherein the particles
are present in the forming size composition in an amount ranging
from 1 to 20 weight percent of the sizing composition on a total
solids basis.
42. A fabric comprising at least one fiber strand according to
claim 29.
43. A fabric comprising at least one fiber strand according to
claim 30.
44. A fabric comprising at least one fiber strand according to
claim 32.
45. A coated fiber strand comprising at least one fiber having a
residue of an aqueous forming size composition applied to at least
a portion of a surface of the at least one fiber, the aqueous
forming size composition comprising: (a) at least one starch; (b)
at least one film-forming material; (c) at least one lubricant; and
(d) a plurality of discrete particles having a Mohs hardness of no
greater than that of the at least one fiber.
46. A fabric comprising a plurality of fiber strands comprising at
least one fiber having a residue of an aqueous forming size
composition applied to at least a portion of a surface of the at
least one fiber, the aqueous forming size composition comprising:
(a) at least one starch; (b) at least one film-forming material;
(c) at least one lubricant; and (d) a plurality of discrete
particles that provide interstitial space between the at least one
fiber and at least one adjacent fiber sufficient to allow wet out
of the fiber strand.
47. The fabric according to claim 46, wherein the strand is
selected from twisted glass fiber strand and non-twisted glass
fiber strand and the fabric is selected from woven fabrics,
nonwoven fabrics and knitted fabrics.
48. An electronic support comprising the fabric according to claim
46.
Description
RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/183,605 filed Feb. 18, 2000.
[0002] This invention relates generally to aqueous forming size
compositions for treating glass fibers including at least one
starch; at least one film forming material; at least one oil, wax
or other lubricant, and selected discrete, dimensionally stable
particles.
[0003] Typically, the surfaces of glass fibers are coated with a
size composition during the forming process to protect the glass
fibers from interfilament abrasion. As used herein, the. terms
"size" or "sizing" means the aqueous forming size composition
applied to glass fibers immediately after formation of the glass
fibers. Such forming size compositions typically include as
components film-formers, lubricants, coupling agents, emulsifiers,
antioxidants, ultraviolet light stabilizers, colorants, antistatic
agents and water, to name a few.
[0004] Sized or treated glass fibers are typically gathered into a
strand, wound to form a forming package, and dried. Optionally, a
secondary coating can be applied to the strands. The strands can be
twisted into a yarn or bulked. Twisted strands can be used as fill
or warp yarn.
[0005] The forming sized strands can be processed into a wide
variety of configurations, for example braids, roving, knits,
tapes, chopped and continuous strand mats, and woven and non-woven
fabrics, useful in many applications, such as cloth for printed
circuit boards for the computer industry, knits for orthopedics or
overwrap reinforcements for optical fiber cables, for example.
[0006] In a weaving operation, the strands must withstand rigorous
processing conditions while maintaining various properties such as
low broken filaments, which can accumulate at contact points such
as guide eyes and tensioning devices, low strand tension, and high
Liability and low insertion time in weaving. Insertion time is the
time it takes from the start of the weaving cycle for fill yarn to
traverse the width of the fabric and pass the selvage, or edge, of
the opposite side of the fabric from the air jet nozzle of the
loom. Fliability refers to the amount of yarn delivered in a
specified time through a loom air jet nozzle held at a fixed air
pressure.
[0007] In addition, since the weaving process can be quite abrasive
to the fiber glass yarns, those yarns used as warp yarns are
typically subjected to a secondary coating step prior to weaving,
commonly referred to as "slashing", to coat the warp yarns with an
abrasion resistance coating (commonly referred to as a "slashing
size") to help minimize abrasive wear of the glass fibers. A
commanly used slashing size is polyvinyl alcohol (PVA). The
slashing size is generally applied over the forming size that was
previously applied to the glass fibers during the fiber forming
operation. As a result, if slashing size is required, the yarn must
also provide adequate penetration of the slashing size into the
strand.
[0008] When glass fibers and glass fiber fabrics are used as
reinforcement for composites or laminates, for example in printed
circuit board applications, it is important that any coating
materials on the fibers be compatible with the polymeric matrix
material into which the fiber strands are incorporated, i.e. the
materials do not require removal prior to incorporation into the
matrix material. However, many sizing components are not compatible
with the polymeric matrix materials and can adversely affect
adhesion between the glass fibers and the polymeric matrix
material. For example, starch, which is a commonly used sizing
component for textile fibers, is generally not compatible with
polymeric matrix material. In addition, typical slashing sizes are
also not generally compatible with the polymeric matrix materials.
As a result, these incompatible materials must be removed from the
fabric prior to impregnation with the polymeric matrix
material.
[0009] The removal of such non-resin compatible sizing materials,
i.e., de-greasing or de-oiling the fabric, can be accomplished
through a variety of techniques. The removal of these non-resin
compatible sizing materials is most commonly accomplished by
exposing the woven fabric to elevated temperatures for extended
periods of time to thermally decompose the sizing(s) (commonly
referred to as heat cleaning). A conventional heat cleaning process
involves heating the fabric at 380.degree. C. for 60-80 hours.
Other methods of removing sizing materials have been tried, such as
water washing and/or chemical removal.
[0010] When glass fibers are used as reinforcement for printed
circuit board applications, and in particular woven glass fabrics,
in addition to the properties discussed above, the fabrics must
also provide effective size removal in heat cleaning (if heat
cleaning is required) and adequate penetration of resin materials
during fabric impregnation. Overwrap reinforcements for optical
fiber cables also must meet stringent requirements in view of the
severe service conditions to which they are exposed.
[0011] It would be advantageous to provide a forming size
composition that would facilitate penetration of the fiber bundles
by a slashing size, if a slashing size is required, and could
reduce, and possibly eliminate, the need to apply a slashing size
by providing adequate abrasion resistance during weaving. In
addition, it would be advantageous to provide a forming size
composition having selected constituents that remain on the fibers
and/or within the fiber bundles after heat cleaning, wherein the
selected constituents are compatible with the resin applied to the
fibers, would facilitate good penetration of the resin when applied
to the fiber strand bundles, and provide protection to the fibers
during subsequent processing.
SUMMARY OF THE INVENTION
[0012] The present invention provides coated fiber strand
comprising at least one fiber having a residue of an aqueous
forming size composition applied to at least a portion of a surface
of the at least one fiber, the aqueous forming size composition
comprising: (a) at least onestarch; (b) at least one film-forming
material; (c) at least one lubricant; and (d) a plurality of
discrete particles that provide interstitial space between the at
least one fiber and at least one adjacent fiber sufficient to allow
wet out of the fiber strand. In one embodiment of the invention,
the fibers are glass fibers, the at least one starch comprises an
oleophobic starch, the at least one film-forming material comprises
a N-vinyl amide polymer; the at least one lubricant comprises an
ester, and the particles are dimensionally stable particles
selected from polymeric organic materials, non-polymeric organic
materials, polymeric inorganic materials, non-polymeric inorganic
materials, composite materials and mixtures thereof. In one
non-limiting embodiment of the invention, the particles comprise
hexagonal boron nitride particles and/or hollow particles formed
from a copolymer of styrene and acrylic monomer.
[0013] The present invention also provides a coated fiber strand
comprising at least one fiber having a residue of an aqueous
forming size composition applied to at least a portion of a surface
of the at least one fiber, the aqueous forming size composition
comprising: (a) at least one starch; (b) at least one film-forming
material; (c) at least one lubricant; and (d) a plurality of
discrete particles having a Mohs hardness of no greater than that
of the at least one fiber.
[0014] The present invention also provides a fabric comprising a
plurality of fiber strands comprising at least one fiber having a
residue of an aqueous forming size composition applied to at least
a portion of a surface of the at least one fiber, the aqueous
forming size composition comprising: (a) at least one starch; (b)
at least one film-forming material; (c) at least one lubricant; and
(d) a plurality of discrete particles that provide interstitial
space between the at least one fiber and at least one adjacent
fiber sufficient to allow wet out of the fiber strand.
[0015] The present invention also provides an electronic support
comprising the fabric.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0016] The aqueous forming size composition of the present
invention provides glass fiber strands having a variety of
advantageous properties, including low broken filaments, low strand
tension, adequate solution penetration during slashing and resin
impregnation, and high fliability and low insertion time during
weaving. Glass fiber strands treated with the aqueous forming size
composition of the present invention can withstand a wide variety
of further processing operations such as twisting, chopping,
forming into a bundle, roving, chopped mat or continuous strand mat
or weaving or knitting into a cloth. Such strands are useful in a
wide variety of applications, such as cloth for printed circuit
boards, knits for orthopedics, and overwrap reinforcements for
optical fiber cables. In addition, retaining selected components of
the forming size composition on the fabric and incorporating the
fabric into prepregs and laminates for electronic supports, such as
printed circuit boards, can potentially improve selected properties
of the prepregs, laminates and printed circuit boards, such as
drillability, i.e. reduced drill tip wear and/or improved drilled
hole location accuracy. More particularly, selected components of
the forming size composition of the present invention can function
as a lubricant during the drilling operation and/or maintain
desired interstitial spacing between adjacent strand fibers. As
used herein, "electronic support" means a structure that
mechanically supports and/or electrically interconnects elements
including but not limited to active electronic components, passive
electronic components, printed circuits, integrated circuits,
semiconductor devices and other hardware associated with such
elements, such as but not limited to connectors, sockets, retaining
clips and heat sinks.
[0017] For the purposes of this specification, other than in the
operating examples, or where otherwise indicated, all numbers
expressing quantities of ingredients, reaction conditions, and so
forth used in the specification and claims are to be understood as
being modified in all instances by the term "about." Accordingly,
unless indicated to the contrary, the numerical parameters set
forth in the following specification and attached claims are
approximations that may vary depending upon the desired properties
sought to be obtained by the present invention. At the very least,
and not as an attempt to limit the application of the doctrine of
equivalents to the scope of the claims, each numerical parameter
should at least be construed in light of the number of reported
significant digits and by applying ordinary rounding
techniques.
[0018] Notwithstanding that the numerical ranges and parameters
setting forth the broad scope of the invention are approximations,
the numerical values set forth in the specific examples are
reported as precisely as possible. Any numerical value, however,
inherently contain certain errors necessarily resulting from the
standard deviation found in their respective testing
measurements.
[0019] As used herein, the term "strand" means a plurality of
individual fibers, i.e., at least two fibers, and the strand can
comprise fibers made of different fiberizable materials (the bundle
of fibers can also be referred to as "yarn"). As used herein, the
term "fiber" means an individual filament. Although not limiting
the present invention, the fibers have an average nominal fiber
diameter ranging from 3 to 35 micrometers.
[0020] The fibers in the present invention can be formed from any
type of fiberizable material known to those skilled in the art
including fiberizable inorganic materials, fiberizable organic
materials and mixtures of any of the foregoing. The inorganic and
organic materials can be either man-made or naturally occurring
materials. One skilled in the art will appreciate that the
fiberizable inorganic and organic materials can also be polymeric
materials. As used herein, the term "polymeric material" means a
material formed from macromolecules composed of long chains of
atoms that are linked together and that can become entangled in
solution or in the solid state.sup.1. As used herein, the term
"fiberizable" means a material capable of being formed into a
generally continuous filament, fiber, strand or yarn.
[0021] In one non-limiting embodiment of the present invention, the
fibers are formed from an inorganic, fiberizable glass material.
Fiberizable glass materials useful in the present invention
include, but are not limited to those prepared from fiberizable
glass compositions such as "E-glass", "A-glass", "C-glass",
"D-glass", "R-glass", "S-glass", and E-glass derivatives. As used
herein, "E-glass derivatives" means glass compositions that include
minor amounts of fluorine and/or boron, and preferably are
fluorine-free and/or boron-free. Furthermore, as used herein,
"minor amounts of fluorine" means less than 0.5 weight percent
fluorine, preferably less than 0.1 weight percent fluorine, and
"minor amounts of boron" means less than 5 weight percent boron,
preferably less than 2 weight percent boron. Basalt and mineral
wool are examples of other fiberizable glass materials useful in
the present invention. In one non-limiting embodiment of the
present invention glass fibers are formed from E-glass or E-glass
derivatives. Such compositions are well known to those skilled in
the art and further discussion thereof is not believed to be
necessary in view of the present disclosure. For additional
information relating to glass compositions and methods of forming
the glass fibers, see K. Loewenstein, The Manufacturing Technology
of Continuous Glass Fibres, (3d Ed. 1993) at pages 30-44, 47-103,
and 115-165; U.S. Pat. Nos. 4,542,106 and 5,789,329; and IPC-EG-140
"Specification for Finished Fabric Woven from `E` Glass for Printed
Boards" at page 1, a publication of The Institute for
Interconnecting and Packaging Electronic Circuits (June 1997),
which are specifically incorporated by reference herein.
[0022] Non-limiting examples of suitable non-glass fiberizable
inorganic materials include ceramic materials such as silicon
carbide, carbon, graphite, mullite, aluminum oxide and
piezoelectric ceramic materials. Non-limiting examples of suitable
fiberizable organic materials include cotton, cellulose, natural
rubber, flax, ramie, hemp, sisal and wool. Non-limiting examples of
suitable fiberizable organic polymeric materials include those
formed from polyamides (such as nylon and aramids), thermoplastic
polyesters (such as polyethylene terephthalate and polybutylene
terephthalate), acrylics (such as polyacrylonitriles), polyolefins,
polyurethanes and vinyl polymers (such as polyvinyl alcohol).
Non-glass fiberizable materials useful in the present invention and
methods for preparing and processing such fibers are discussed at
length in the Encyclopedia of Polymer Science and Technology, Vol.
6 (1967) at pages 505-712, which is specifically incorporated by
reference herein.
[0023] It is understood that blends or copolymers of any of the
above materials and combinations of fibers formed from any of the
above materials can be used in the present invention, if desired.
Moreover, the term strand encompasses at least two different fibers
made from differing fiberizable materials. In one non-limiting
embodiment of the present invention, the fiber strands contain at
least one glass fiber, although they may contain other types of
fibers.
[0024] The present invention will now be discussed generally in the
context of glass fiber strands, although one skilled in the art
would understand that the strand can comprise fibers formed from
any fiberizable material known in the art as discussed above. Thus,
the discussion that follows in terms of glass fibers applies
generally to the other fibers discussed above.
[0025] At least one and preferably all of the fibers of a fiber
strand of the present invention have a layer of a forming size
composition, preferably a residue of a forming size composition, on
at least a portion of the surfaces of the fibers. The layer can be
present on portions or on the entire outer surface or periphery of
the fibers.
[0026] The aqueous forming size composition of the present
invention comprises at least one starch; at least one oil, wax or
other lubricant; and selected particles that provide desired
properties to the yarn and/or fabric such as, but not limited to,
desired interstitial spacing between adjacent fibers and abrasion
resistance. The forming size composition can also include at least
one film forming material, wetting agent, emulsifying agent,
defoamer, humectant, biocide and/or any other conventional material
known to those skilled in the art. Non-limiting examples of size
compositions are set forth in U.S. Pat. Nos. 5,354,829 and
5,773,146 and K. Loewenstein, The Manufacturing Technology of
Continuous Glass Fibres (3d Ed. New York 1983) at page 238-244,
which are hereby incorporated by reference.
[0027] Non-limiting examples of starches useful in the present
invention include those derived from potatoes, corn, wheat, waxy
maize, sago, milo, tapioca or rice. Such starches can have high or
low amylose contents and high or low viscosity. The starches of the
present invention can be modified by acetylation, chlorination,
acid hydrolysis, derivatizing agents, crosslinking agents or
enzymatic action, for example. As used herein, the term "high
amylose content" means a starch having an amylose content of at
least 40 weight percent on a total solids basis, and the term "low
amylose content" means a starch having an amylose content of up to
40 weight percent on a total solids basis, and preferably 10 to 40
weight percent. Although not limiting herein, starches having high
amylose contents are typically derived from corn starch or hybrid
corn starch, whereas starches having a low amylose content can be
derived from potato, tapioca or modified corn starches. As used
herein, the term "low-viscosity starch" means a starch with a
post-cook viscosity of 100 centipoise or less at a temperature of
38.degree. C. (100.degree. F.) and a 6 percent solids level, and
the term "high-viscosity starch" means a starch with a post-cook
viscosity greater than or equal to 100 centipoise at a temperature
of 38.degree. C. (100.degree. F.) and a 6 percent solids level. The
viscosity is measured using a No. 61 spindle on a Brookfield
Viscometer Model No. DV2+ at about 12 revolutions per minute (rpm).
In one non-limiting embodiment of the present invention, the starch
component of the forming size composition comprises 50 to 90 weight
percent of a high viscosity starch.
[0028] Although not limiting in the present invention, in one
embodiment the starch is an "oleophobic starches" which as used
herein means those starches which are not compatible with, do not
have an affinity for and/or are not capable of dissolving in, yet
can be dispersed in, solid predominately hydrocarbon unctuous
materials, such as a wax, fat or gelled oil.
[0029] Non-limiting examples of useful oleophobic starches include
KOLLOTEX 1250 starch, which is a low viscosity, low amylose
potato-based starch etherified with ethylene oxide which is
commercially available from AVEBE of the Netherlands: NATIONAL 1554
starch, which is a high viscosity, low amylose crosslinked potato
starch; HI-SET 369 starch, which is a low viscosity starch, HYLON
and NABOND starches, which are high viscosity starches, each of
which are commercially available from National Starch and Chemical
Corp. of Bridgewater, N.J.; and AMAIZO 213 starch, which is a high
viscosity, crosslinked starch and other AMAIZO starches, which are
commercially available from American Maize Products Company of
Hammond, Ind. HI-SET 369 is a propylene oxide modified corn starch
having an amylose/amylopectin ratio of 55/45.
[0030] Although not limiting in the present invention, in one
particular embodiment, the starch is a blend of oleophobic
starches, such as but not limited to, a blend of NATIONAL 1554 and
AMAIZO 213 starches, or a blend of NATIONAL 1554 and HI-SET 369
starches. In another non-limiting embodiment, a single starch such
as, but not limited to KOLLOTEX 1250 starch, is used.
[0031] In one non-limiting embodiment of the present invention, the
total percentage of starch in the forming size composition ranges
from 10 to 90 weight percent on a total solids basis. In another
non-limiting embodiment, the total percentage of starch in the
forming size composition ranges from 30 to about 75 weight percent
on a total solids basis. In still another non-limiting embodiment,
the total percentage of starch in the forming size composition
ranges from 40 to 65 weight percent on a total solids basis.
[0032] Although not required, the aqueous forming size composition
can also comprises additional film-forming materials. In one
non-limiting embodiment of the present invention, the additional
film forming materials comprise thermosetting materials,
thermoplastic materials, and combinations thereof that form a
generally continuous film when applied to the surface of the glass
fibers.
[0033] Useful thermosetting materials include, but are not limited
to, thermosetting polyesters, epoxy materials, vinyl esters,
phenolics, aminoplasts, thermosetting polyurethanes and mixtures
thereof. Non-limited examples of suitable thermosetting polyesters
include STYPOL polyesters, which are commercially available from
Cook Composites and Polymers of Kansas City, Mo., and NEOXIL
polyesters, which are commercially available from DSM B.V. of Como,
Italy. Useful epoxy materials contain at least one epoxy or oxirane
group in the molecule, such as, but not limited to, polyglycidyl
ethers of polyhydric alcohols or thiols. Non-limiting examples of
suitable epoxy film-forming polymers include EPON.RTM. 826 and
EPON.RTM. 880 epoxy resins, which are commercially available from
Shell Chemical Company of Houston, Tex.
[0034] Non-limiting examples of useful thermoplastic polymeric
materials include vinyl polymers, thermoplastic polyesters,
polyolefins, polyamides (e.g. aliphatic polyamides or aromatic
polyamides such as aramid), thermoplastic polyurethanes, acrylic
polymers and mixtures thereof. In one non-limiting embodiment of
the present invention, vinyl polymers useful in the present
invention are N-vinyl amide polymers. In another non-limiting
embodiment, the vinyl polymers are polyvinyl pyrrolidones such as
PVP K-15, PVP K-30, PVP K-60 and PVP K-90, each of which are
commercially available from International Specialty Products
Chemicals of Wayne, N.J. Other non-limiting examples of suitable
vinyl polymers include RESYN 2828 and RESYN 1037 vinyl acetate
copolymer emulsions, which are commercially available from National
Starch, and other polyvinyl acetates such as are commercially
available from H. B. Fuller and Air Products and Chemicals Co. of
Allentown, Pa.
[0035] A non-limiting example of a useful polyvinyl pyrrolidone
copolymer is PVPNA S-630 polyvinyl pyrrolidone/vinyl acetate
copolymer, which is commercially available from International
Specialty Products Chemicals of Wayne, N.J.
[0036] Other thermoplastic polyesters useful in the present
invention include, but are not limited to, DESMOPHEN 2000 and
DESMOPHEN 2001KS polyesters, both of which are commercially
available from Bayer Corp. of Pittsburgh, Pa. Polyesters useful in
the present invention include, but are not limited to, RD-847A
polyester resin, which is commercially available from Borden
Chemicals of Columbus, Ohio, and DYNAKOLL Si 100 chemically
modified rosin, which is commercially available from Eka Chemicals
AB, Sweden. Useful polyamides include, but are not limited to, the
VERSAMID products, which are commercially available from Cognis
Corp. of Cincinnati, Ohio, and the EUREDOR products that are
available from Ciba Geigy, Belgium. Useful thermoplastic
polyurethanes include WITCOBOND.RTM. W-290H, which is commercially
available from Crompton Corporation of Greenwich, Conn., and
RUCOTHANE.RTM. 2011L polyurethane latex, which is commercially
available from Ruco Polymer Corp. of Hicksville, N.Y.
[0037] The aqueous forming size composition of the present
invention can comprise a mixture of one or more thermosetting
polymeric materials with one or more thermoplastic polymeric
materials.
[0038] The additional film-forming material is present in the
aqueous forming size composition in an amount ranging from 0.1 to
30 weight percent on a total solids basis. In one non-limiting
embodiment, the additional film-forming material is present in the
aqueous forming size composition in an amount ranging from 1 to 10
weight percent on a total solids basis. In another non-limiting
embodiment, the additional film-forming material is present in the
aqueous forming size composition in an amount ranging from 3 to 8
weight percent on a total solids basis.
[0039] The forming sizing composition of the present invention
further comprises one or more, and preferably a plurality of
particles that when applied to at least one fiber of the plurality
of fibers adhere to the outer surface of the at least one fiber and
provide one or more interstitial spaces between adjacent glass
fibers of the strand. These interstitial spaces correspond
generally to the size of the particles positioned between the
adjacent fibers.
[0040] In one non-limiting embodiment of the present invention, the
particles are discrete particles. As used herein, the term
"discrete" means that the particles do not tend to coalesce or
combine to form continuous films under conventional processing
conditions, but instead substantially retain their individual
distinctness, and generally retain their individual shape or form.
The discrete particles of the present invention can undergo
shearing, i.e., the removal of a layer or sheet of atoms in a
particle, necking, i.e. a second order phase transition between at
least two particles, and partial coalescence during conventional
fiber processing, and still be considered to be "discrete"
particles.
[0041] In one non-limiting embodiment of the present invention, the
particles are dimensionally stable. As used herein, the term
"dimensionally stable particles" means that the particles will
generally maintain their average particle size and shape under
conventional fiber processing conditions, such as the forces
generated between adjacent fibers during weaving, roving and other
processing operations, so as to maintain the desired interstitial
spaces between adjacent fibers. In other words, dimensionally
stable particles preferably will not crumble, dissolve or
substantially deform in the sizing composition to form a particle
having a maximum dimension less than its selected average particle
size under typical glass fiber processing conditions, such as
exposure to temperatures of up to 25.degree. C., preferably up to
100.degree. C., and more preferably up to 140.degree. C.
Additionally, the particles should not substantially enlarge or
expand in size under glass fiber processing conditions and, more
particularly, under composite processing conditions where the
processing temperatures can exceed 150.degree. C. As used herein,
the phrase "should not substantially enlarge in size" in reference
to the particles means that the particles should not expand or
increase in size to more than approximately three times their
initial size during processing. Furthermore, as used herein, the
term "dimensionally stable particles" covers both crystalline and
non-crystalline particles.
[0042] In one non-limiting embodiment of the invention, the
particles of the sizing compositions are substantially free of heat
expandable particles. As used herein, the term "heat expandable
particles" means particles filled with or containing a material,
which, when exposed to temperatures sufficient to volatilize the
material, expand or substantially enlarge in size. These heat
expandable particles therefore expand due to a phase change of the
material in the particles, e.g., a blowing agent, under normal
processing conditions. Consequently, the term "non-heat expandable
particle" refers to a particle that does not expand due a phase
change of the material in the particle under normal fiber
processing conditions, and in one non-limiting embodiment of the
present invention, the forming sizing compositions comprise at
least one non-heat expandable particle. Generally, the heat
expandable particles are hollow particles with a central cavity. In
a non-limiting embodiment of the present invention, the cavity can
be at least partial filled with a non-solid material such as a gas,
liquid, and/or a gel. As used herein, the term "substantially free
of heat expandable particles" means less than 50 weight percent of
heat expandable particles on a total solids basis, more preferably
less than 35 weight percent. In one non-limiting embodiment, the
sizing compositions of the present invention are essentially free
of heat expandable particles. As used herein, the term "essentially
free of heat expandable particles" means the sizing composition
comprises less than 20 weight percent of heat expandable particles
on a total solids basis, more preferably less than 5 weight
percent, and most preferably less than 0.001 weight percent.
[0043] In one non-limiting embodiment of the sizing compositions,
the particles are non-waxy. The term "non-waxy" means the materials
from which the particles are formed are not wax-like. As used
herein, the term "wax-like" means materials composed primarily of
unentangled hydrocarbons chains having an average carbon chain
length ranging from 25 to 100 carbon atoms.sup.2,3.
[0044] In another non-limiting embodiment of the present invention,
the particles in are discrete, dimensionally stable, non-waxy
particles.
[0045] The particles can have any shape or configuration desired.
Although not limiting in the present invention, examples of
suitable particle shapes include spherical (such as beads,
microbeads or hollow spheres), cubic, platy or acicular (elongated
or fibrous). Additionally, the particles can have an internal
structure that is hollow, porous or void free, or a combination
thereof, e.g. a hollow center with porous or solid walls. For more
information on suitable particle characteristics see H. Katz et al.
(Ed.), Handbook of Fillers and Plastics (1987) at pages 9-10, which
are specifically incorporated by reference herein.
[0046] The particles can be formed from materials selected from
polymeric inorganic materials, non-polymeric inorganic materials,
polymeric organic materials, non-polymeric organic materials,
composite materials, and mixtures of any of the foregoing. As used
herein, the term "polymeric inorganic material" means a polymeric
material having a backbone repeat unit based on an element or
elements other than carbon. For more information see J. E. Mark et
al. at page 5, which is specifically incorporated by reference
herein. As used herein, the term "polymeric organic materials"
means synthetic polymeric materials, semisynthetic polymeric
materials and natural polymeric materials having a backbone repeat
unit based on carbon.
[0047] An "organic material", as used herein, means carbon
containing compounds wherein the carbon is typically bonded to
itself and to hydrogen, and often to other elements as well, and
excludes binary compounds such as the carbon oxides, the carbides,
carbon disulfide, etc.; such ternary compounds as the metallic
cyanides, metallic carbonyls, phosgene, carbonyl sulfide, etc.; and
carbon-containing ionic compounds such as the metallic carbonates,
such as calcium carbonate and sodium carbonate. As used herein, the
term "inorganic materials" means any material that is not an
organic material. See R. Lewis, Sr., Hawley's Condensed Chemical
Dictionary, (12th Ed. 1993) at pages 761-762, and M. Silberberg,
Chemistry The Molecular Nature of Matter and Change (1996) at page
586, which are specifically incorporated by reference herein.
[0048] As used herein, the term "composite material" means a
combination of two or more differing materials. The particles
formed from composite materials generally have a hardness at their
surface that is different from the hardness of the internal
portions of the particle beneath its surface. More specifically,
the surface of the particle can be modified in any manner well
known in the art, including, but not limited to, chemically or
physically changing its surface characteristics using techniques
known in the art, such that the surface hardness of the particle is
equal to or less than the hardness of the glass fibers while the
hardness of the particle beneath the surface is greater than the
hardness of the glass fibers. For example, a particle can be formed
from a primary material that is coated, clad or encapsulated with
one or more secondary materials to form a composite particle that
has a softer surface. In yet another alternative embodiment,
particles formed from composite materials can be formed from a
primary material that is coated, clad or encapsulated with a
different form of the primary material. For more information on
particles useful in the present invention, see G. Wypych, Handbook
of Fillers, 2nd Ed. (1999) at pages 15-202, which are specifically
incorporated by reference herein.
[0049] Representative non-polymeric, inorganic materials useful in
forming the particles of the present invention include, but are not
limited to, inorganic materials selected from graphite, metals,
oxides, carbides, nitrides, borides, sulfides, silicates,
carbonates, sulfates and hydroxides. A non-limiting example of a
suitable inorganic nitride from which the particles are formed is
boron nitride. In one non-limiting embodiment of the particles, the
boron nitride particles have a hexagonal crystal structure. A
non-limiting example of a useful inorganic oxide is zinc oxide.
Suitable inorganic sulfides include, but are not limited to,
molybdenum disulfide, tantalum disulfide, tungsten disulfide and
zinc sulfide. Useful inorganic silicates include, but are not
limited to, aluminum silicates and magnesium silicates, such as
vermiculite. Suitable metals include, but are not limited to,
molybdenum, platinum, palladium, nickel, aluminum, copper, gold,
iron, silver, alloys, and mixtures of any of the foregoing.
[0050] In one non-limiting embodiment of the invention, the
particles are formed from solid lubricant materials. As used
herein, the term "solid lubricant" means any solid used between two
surfaces to provide protection from damage during relative movement
and/or to reduce friction and wear. In one non-limiting embodiment,
the solid lubricants are inorganic solid lubricants. As used
herein, "inorganic solid lubricant" means that the solid lubricants
have a characteristic crystalline habit which causes them to shear
into thin, flat plates which readily slide over one another and
thus produce an antifriction lubricating effect between the fiber
surfaces, preferably the glass fiber surface, and an adjacent solid
surface, at least one of which is in motion. See R. Lewis, Sr.,
Hawley's Condensed Chemical Dictionary, (12th Ed. 1993) at page
712, which is specifically incorporated by reference herein.
Friction is the resistance to sliding one solid over another. See
F. Clauss, Solid Lubricants and Self-Lubricating Solids (1972) at
page 1, which is specifically incorporated by reference herein.
[0051] In one non-limiting embodiment of the invention, the
particles have a lamellar structure. Particles having a lamellar
structure are composed of sheets or plates of atoms in hexagonal
array, with strong bonding within the sheet and weak van der Waals
bonding between sheets, providing low shear strength between
sheets. A non-limiting example of a lamellar structure is a
hexagonal crystal structure. See K. Ludema, Friction, Wear,
Lubrication (1996) at page 125, Solid Lubricants and
Self-Lubricating Solids at pages 19-22, 42-54, 75-77, 80-81, 82,
90-102, 113-120 and 128; and W. Campbell, "Solid Lubricants",
Boundary Lubrication; An Appraisal of World Literature, ASME
Research Committee on Lubrication (1969) at pages 202-203, which
are specifically incorporated by reference herein. Inorganic solid
particles having a lamellar fullerene (buckyball) structure are
also useful in the present invention.
[0052] Non-limiting examples of suitable materials having a
lamellar structure that are useful in forming the particles of the
present invention include boron nitride, graphite, metal
dichalcogenides, mica, talc, gypsum, kaolinite, calcite, cadmium
iodide, silver sulfide, and mixtures of any of the foregoing. In
one non-limiting embodiment of the present invention, the suitable
materials include boron nitride, graphite, metal dichalcogenides,
and mixtures of any of the foregoing. Suitable metal
dichalcogenides include molybdenum disulfide, molybdenum
diselenide, tantalum disulfide, tantalum diselenide, tungsten
disulfide, tungsten diselenide, and mixtures of any of the
foregoing.
[0053] In one non-limiting embodiment, the particles are formed
from an inorganic solid lubricant material having a lamellar
structure. A non-limiting example of an inorganic solid lubricant
material having a lamellar structure for use in the sizing
compositions of the present invention is boron nitride, for example
boron nitride having a hexagonal crystal structure. Particles
formed from boron nitride, zinc sulfide and montmorillonite also
provide good whiteness in composites with polymeric matrix
materials such as nylon 6,6.
[0054] Non-limiting examples of particles formed from boron nitride
that are suitable for use in the present invention are
POLARTHERM.RTM. 100 Series (PT 120, PT 140, PT 160 and PT 180); 300
Series (PT 350) and 600 Series (PT 620, PT 630, PT 640 and PT 670)
boron nitride powder particles, commercially available from
Advanced Ceramics Corporation of Lakewood, Ohio. "PolarTherm.RTM.
Thermally Conductive Fillers for Polymeric Materials", a technical
bulletin of Advanced Ceramics Corporation of Lakewood, Ohio (1996),
which is specifically incorporated by reference herein. These
particles have a thermal conductivity of 250-300 Watts per meter
.degree. K at 25.degree. C., a dielectric constant of 3.9 and a
volume resistivity of 10.sup.15 ohm-centimeters. The 100 Series
powder particles have an average particle size ranging from 5 to 14
micrometers, the 300 Series powder particles have an average
particle size ranging from 100 to 150 micrometers and the 600
Series powder particles have an average particle size ranging from
16 to greater than 200 micrometers. In particular, as reported by
its supplier, POLARTHERM 160 particles have an average particle
size of 6 to 12 micrometers, a particle size range of submicrometer
to 70 micrometers, and a particle size distribution as follows:
1 % > 10 50 90 Size (.mu.m) 18.4 7.4 0.6
[0055] According to this distribution, ten percent of the
POLARTHERM.RTM. 160 boron nitride particles that were measured had
an average particle size greater than 18.4 micrometers. As used
herein, the "average particle size" refers to the mean particle
size of the particles.
[0056] The average particle size of the particles according to the
present invention can be measured according to known laser
scattering techniques. In one non-limiting embodiment of the
present invention, the particles size is measured using a Beckman
Coulter LS 230 laser diffraction particle size instrument, which
uses a laser beam with a wave length of 750 nm to measure the size
of the particles and assumes the particle has a spherical shape,
i.e. the "particle size" refers to the smallest sphere that will
completely enclose the particle. For example, particles of
POLARTHERM.RTM. 160 boron nitride particles measured using the
Beckman Coulter LS 230 particle size analyzer were found to have an
average particle size of 11.9 micrometers with particles ranging
from submicrometer to 35 micrometers and having the following
distribution of particles:
2 % > 10 50 90 Size (.mu.m) 20.6 11.3 4.0
[0057] According to this distribution, ten percent of the
POLARTHERM.RTM. 160 boron nitride particles that were measured had
an average particle size greater than 20.6 micrometers.
[0058] In another non-limiting embodiment of the present invention,
the particles are formed from inorganic materials that are
non-hydratable. As used herein, "non-hydratable" means that the
inorganic particles do not react with molecules of water to form
hydrates and do not contain water of hydration or water of
crystallization. A "hydrate" is produced by the reaction of
molecules of water with a substance in which the H--OH bond is not
split. See R. Lewis, Sr., Hawley's Condensed Chemical Dictionary,
(12th Ed. 1993) at pages 609-610 and T. Perros, Chemistry, (1967)
at pages 186-187, which are specifically incorporated by reference
herein. In the formulas of hydrates, the addition of the water
molecules is conventionally indicated by a centered dot, e.g.,
3MgO.cndot.4SiO.sub.2.c- ndot.H.sub.2O (talc),
Al.sub.2O.sub.3.cndot.2SiO.sub.2.cndot.2H.sub.2O (kaolinite).
Structurally, hydratable inorganic materials include at least one
hydroxyl group within a layer of a crystal lattice (but not
including hydroxyl groups in the surface planes of a unit structure
or materials which absorb water on their surface planes or by
capillary action), for example as shown in the structure of
kaolinite given in FIG. 3.8 at page 34 of J. Mitchell, Fundamentals
of Soil Behavior (1976) and as shown in the structure of 1:1 and
2:1 layer minerals shown in FIGS. 18 and 19 +L, respectively, of H.
van Olphen, Clay Colloid Chemistry, (2d Ed. 1977) at page 62, which
are specifically incorporated by reference herein. A "layer" of a
crystal lattice is a combination of sheets, which is a combination
of planes of atoms. (See Minerals in Soil Environments, Soil
Science Society of America (1977) at pages 196-199, which is
specifically incorporated by reference herein). The assemblage of a
layer and interlayer material (such as cations) is referred to as a
unit structure.
[0059] Hydrates contain coordinated water, which coordinates the
cations in the hydrated material and cannot be removed without the
breakdown of the structure, and/or structural water, which occupies
interstices in the structure to add to the electrostatic energy
without upsetting the balance of charge. R. Evans, An Introduction
to Crystal Chemistry (1948) at page 276, which is specifically
incorporated by reference herein. In one non-limiting embodiment of
the present invention, the sizing composition is preferably
essentially free of hydratable particles. As used herein, the term
"essentially free of hydratable particles" means the sizing
composition comprises less than 20 weight percent of hydratable
particles on a total solids basis, more preferably less than 5
weight percent, and most preferably less than 0.001 weight percent.
In one non-limiting embodiment of the present invention, the
particles are formed from a non-hydratable, inorganic solid
lubricant material.
[0060] The forming size compositions according to the present
invention can contain particles formed from hydratable or hydrated
inorganic materials in lieu of or in addition to the non-hydratable
inorganic materials discussed above. Non-limiting examples of such
hydratable inorganic materials are clay mineral phyllosilicates,
including micas (such as muscovite), talc, montmorillonite,
kaolinite and gypsum.
[0061] In another non-limiting embodiment of the present invention,
the particles can be formed from non-polymeric, organic materials.
Examples of non-polymeric, organic materials useful in the present
invention include, but are not limited to, stearates (such as zinc
stearate and aluminum stearate), carbon black and stearamide.
[0062] In yet another non-limiting embodiment of the present
invention, the particles can be formed from inorganic polymeric
materials. Non-limiting examples of useful inorganic polymeric
materials include polyphosphazenes, polysilanes, polysiloxane,
polygeremanes, polymeric sulfur, polymeric selenium, silicones, and
mixtures of any of the foregoing. A specific non-limiting example
of a particle formed from an inorganic polymeric material suitable
for use in the present invention is TOSPEARL.sup.4, which is a
particle formed from cross-linked siloxanes and is commercially
available from Toshiba Silicones Company, Ltd. of Japan.
[0063] In still another non-limiting embodiment of the present
invention, the particles can be formed from synthetic, organic
polymeric materials. Suitable organic polymeric materials include,
but are not limited to, thermosetting materials and thermoplastic
materials. Suitable thermosetting materials include, but are not
limited to, thermosetting polyesters, vinyl esters, epoxy
materials, phenolics, aminoplasts, thermosetting polyurethanes, and
mixtures of any of the foregoing. A non-limiting example of a
synthetic polymeric particle formed from an epoxy material is an
epoxy microgel particle.
[0064] Suitable thermoplastic materials include, but are not
limited to, thermoplastic polyesters, polycarbonates, polyolefins,
acrylic polymers, polyamides, thermoplastic polyurethanes, vinyl
polymers, and mixtures of any of the foregoing. Suitable
thermoplastic polyesters include, but are not limited to,
polyethylene terephthalate, polybutylene terephthalate and
polyethylene naphthalate. Suitable polyolefins include, but are not
limited to, polyethylene, polypropylene and polyisobutene. Suitable
acrylic polymers include, but are not limited to, copolymers of
styrene and acrylic monomer and polymers containing methacrylate.
Non-limiting examples of synthetic polymeric particles formed from
an acrylic copolymer are RHOPLEX.RTM. B-85.sup.5, which is an
opaque, non-crosslinking solid acrylic particle emulsion,
ROPAQUE.RTM. HP-1055.sup.6, which is an opaque, non-film-forming,
styrene acrylic polymeric synthetic pigment having a 1.0 micrometer
particle size, a solids content of 26.5 percent by weight and a 55
percent void volume, ROPAQUE.RTM. OP-96.sup.7 and ROPAQUE.RTM.
HP-543P.sup.8, which are identical, each being an opaque,
non-film-forming, styrene acrylic polymeric synthetic pigment
dispersion having a particle size of 0.55 micrometers and a solids
content of 30.5 percent by weight, and ROPAQUE.RTM. OP-62 LO.sup.9
which is also an opaque, non-film-forming, styrene acrylic
polymeric synthetic pigment dispersion having a particles size of
0.40 micrometers and a solids content of 36.5 percent by weight.
Each of these particles is commercially available from Rohm and
Haas Company of Philadelphia, Pa.
[0065] The particles according to the present invention can also be
formed from semisynthetic, organic polymeric materials and natural
polymeric materials. As used herein, a "semisynthetic material" is
a chemically modified, naturally occurring material. Suitable
semisynthetic, organic polymeric materials from which the particles
can be formed include, but are not limited to, cellulosics, such as
methylcellulose and cellulose acetate; and modified starches, such
as starch acetate and starch hydroxyethyl ethers. Suitable natural
polymeric materials from which the particles can be formed include,
but are not limited to, polysaccharides, such as starch;
polypeptides, such as casein; and natural hydrocarbons, such as
natural rubber and gutta percha.
[0066] In one non-limiting embodiment of the present invention, the
polymeric particles are formed from hydrophobic polymeric materials
to reduce or limit moisture absorption by the coated strand.
Non-limiting examples of such hydrophobic polymeric materials
include but are not limited to polyethylene, polypropylene,
polystyrene and polymethylmethacrylate. Non-limiting examples of
polystyrene copolymers include ROPAQUE.RTM. HP-1055, ROPAQUE.RTM.
OP-96, ROPAQUE.RTM. HP-543P, and ROPAQUE.RTM.OP-62 LO pigments
(each discussed above).
[0067] In another non-limiting embodiment of the present invention,
polymeric particles are formed from polymeric materials having a
glass transition temperature (T.sub.g) and/or melting point greater
than 25.degree. C. In still another non-limiting embodiment of the
present invention, polymeric particles are formed from polymeric
materials having a glass transition temperature (T.sub.g) and/or
melting point preferably greater than 50.degree. C.
[0068] In another non-limiting embodiment of the present invention,
the particles can be hollow particles formed from materials
selected from polymeric and non-polymeric inorganic materials,
polymeric and non-polymeric organic materials, composite materials,
and mixtures of any of the foregoing. Non-limiting examples of
suitable materials from which the hollow particles can be formed
are described above. Non-limiting examples of a hollow polymeric
particle useful in present invention are ROPAQUE.RTM. HP-1055,
ROPAQUE.RTM. OP-96, ROPAQUE.RTM. HP-543P, and ROPAQUE.RTM. OP-62 LO
pigments (each discussed above). For other non-limiting examples of
hollow particles that can be useful in the present invention see H.
Katz et al. (Ed.) (1987) at pages 437-452, which are specifically
incorporated by reference herein.
[0069] The particles useful in the forming size composition of
present invention can be present in a dispersion, suspension or
emulsion in water. Other solvents, such as mineral oil or alcohol
(preferably less than 5 weight percent), can be included in the
dispersion, suspension or emulsion, if desired. A non-limiting
example of a dispersion of particles formed from an inorganic
material is ORPAC BORON NITRIDE RELEASECOAT-CONC, which is a
dispersion of 25 weight percent boron nitride particles in water
and is commercially available from ZYP Coatings, Inc. of Oak Ridge,
Tenn. See "ORPAC BORON NITRIDE RELEASECOAT-CONC", a technical
bulletin of ZYP Coatings, Inc., which is specifically incorporated
by reference herein. According to this technical bulletin, the
boron nitride particles in this product have an average particle
size of less than 3 micrometers and include 1 percent of
magnesium-aluminum silicate to bind the boron nitride particles to
the substrate to which the dispersion is applied. Independent
testing of the ORPAC BORON NITRIDE RELEASECOAT-CONC 25 boron
nitride using the Beckman Coulter LS 230 particle size analyzer
found an average particle size of 6.2 micrometers, with particles
ranging from submicrometer to 35 micrometers and having the
following distribution of particles:
3 % > 10 50 90 Size (.mu.m) 10.2 5.5 2.4
[0070] According to this distribution, ten percent of the ORPAC
BORON NITRIDE RELEASECOAT-CONC 25 boron nitride particles that were
measured had an average particle size greater than 10.2
micrometers.
[0071] Other useful products which are commercially available from
ZYP Coatings include BORON NITRIDE LUBRICOAT.RTM. paint, and BRAZE
STOP and WELD RELEASE products. Specific, non-limiting examples of
emulsions and dispersions of synthetic polymeric particles formed
from acrylic polymers and copolymers include: RHOPLEX.RTM. B-85
acrylic emulsion (discussed above), RHOPLEX.RTM. GL-623.sup.10
which is an all acrylic firm polymer emulsion having a solids
content of 45 percent by weight and a glass transition temperature
of 98.degree. C.; EMULSION E-2321.sup.11 which is a hard,
methacrylate polymer emulsion having a solids content of 45 percent
by weight and a glass transition temperature of 105.degree. C.;
ROPAQUE.RTM. OP-96 and ROPAQUE.RTM.) HP-543P (discussed above),
which are supplied as a dispersion having a particle size of 0.55
micrometers and a solids content of 30.5 percent by weight;
ROPAQUE.RTM. OP-62 LO (discussed above), which is supplied as a
dispersion having a particles size of 0.40 micrometers and a solids
content of 36.5 percent by weight; and ROPAQUE.RTM. HP-1055
(discussed above), which is supplied as a dispersion having a
solids content of 26.5 percent by weight; all of which are
commercially available from Rohm and Haas Company of Philadelphia,
Pa. .sup.10 See product property sheet entitled: "Rhoplex+200
GL-623, Self-Crosslinking Acrylic Binder of Industrial Nonwovens",
March 1997 available from Rohm and Haas Company, Philadelphia, Pa.,
which is hereby incorporated by reference. .sup.11 See product
sheet entitled: "Building Products Industrial Coatings- Emulson
E-2321", 1990, available from Rohm and Haas Company, Philadelphia,
Pa., which is hereby incorporated by reference.
[0072] In one non-limiting embodiment of the present invention, the
sizing composition comprises a mixture of at least one inorganic
particle, particularly boron nitride, and more particularly a boron
nitride available under the tradename POLARTHERM.RTM. and/or ORPAC
BORON NITRIDE RELEASECOAT-CONC, and at least one thermoplastic
material, particularly a copolymer of styrene and acrylic monomer,
and more particularly a copolymer available under the tradename
ROPAQUE.RTM..
[0073] The particles are selected to achieve an average particle
size sufficient to effect the desired spacing between adjacent
fibers. For example, in one non-limiting embodiment of the present
invention the average size of the particles incorporated into a
forming size composition applied to fibers to be processed on
air-jet looms is preferably selected to provide sufficient spacing
between at least two adjacent fibers to permit air-jet transport of
the fiber strand across the loom. As used herein, "air-jet loom"
means a type of loom in which the fill yarn (weft) is inserted into
the warp shed by a blast of compressed air from one or more air jet
nozzles in a manner well known to those skilled in the art.
[0074] In another non-limiting embodiment, the average size of the
particles incorporated into a forming size composition applied to
fibers to be impregnated with a polymeric matrix material is
selected to provide sufficient spacing between at least two
adjacent fibers to permit good wet-out and wet-through of the fiber
strand. As used herein, the term "wet-out" means the ability of a
material, for example a slashing solution or a polymeric matrix
material, to penetrate through the individual bundles or strands of
fibers, and the term "wet-through" means the ability of a material,
for example a polymeric matrix material, to penetrate through the
fabric.
[0075] Although not limiting in the present invention, in one
embodiment the particles have an average size, measured using laser
scattering techniques, of no greater than 1000 micrometers. In
another non-limiting embodiment, the particles have an average
size, measured using laser scattering techniques, ranging from
0.001 to 100 micrometers. In another non-limiting embodiment, the
particles have an average size, measured using laser scattering
techniques, ranging from 0.1 to 25 micrometers.
[0076] In another non-limiting embodiment of the present invention,
the average particle size, measured using laser scattering
techniques, is at least 0.1 micrometers and in one non-limiting
embodiment ranges from 0.1 micrometers to 10 micrometers and in
another non-limiting embodiment ranges from 0.1 micrometers to 5
micrometers. In another non-limiting embodiment, the average
particle size of the particles, measured using laser scattering
techniques, is at least 0.5 micrometers and ranges from 0.5
micrometers to 2 micrometers. In another non-limiting embodiment of
the present invention, the particles have an average particle size
that is generally smaller than the average diameter of the fibers
which the sizing composition is applied. It has been observed that
twisted yarns made from fiber strands having a layer of a residue
of a forming size composition comprising particles having average
particles sizes discussed above can advantageously provide
sufficient spacing between adjacent fibers to permit air-jet
weavability (i.e., air-jet transport across the loom) while
maintaining the integrity of the fiber strand and providing
acceptable wet-through and wet-out characteristics when impregnated
with a polymeric matrix material.
[0077] In another non-limiting embodiment of the present invention,
the average particles size, measured using laser scattering
techniques, is at least 3 micrometers and ranges from 3 to 1000
micrometers. In another non-limiting embodiment, the average
particle size, measured using laser scattering techniques, is at
least 5 micrometers and ranges from 5 to 1000 micrometers. In still
another non-limiting embodiment, the particle size ranges from 10
to 25 micrometers, measured using laser scattering techniques. In
another non-limiting embodiment, the average particle size
corresponds generally to the average nominal diameter of the glass
fibers. It has been observed that fabrics made with strands coated
with particles falling within the sizes discussed above exhibit
good wet-through and wet-out characteristics when impregnated with
a polymeric matrix material.
[0078] It will be recognized by one skilled in the art that
mixtures of one or more particles having different average particle
sizes can be incorporated into the sizing composition in accordance
with the present invention to impart the desired properties and
processing characteristics to the fiber strands and to the products
subsequently made therefrom. More specifically, different sized
particles can be combined in appropriate amounts to provide strands
having good air-jet transport properties as well to provide a
fabric exhibiting good wet-out and wet-through characteristics.
[0079] Fibers are subject to abrasive wear by contact with
asperities of adjacent fibers and/or other solid objects or
materials which the glass fibers contact during forming and
subsequent processing, such as weaving or roving. "Abrasive wear",
as used herein, means scraping or cutting off of bits of the fiber
surface or breakage of fibers by frictional contact with particles,
edges or entities of materials which are hard enough to produce
damage to the fibers. See K. Ludema at page 129, which is
specifically incorporated by reference herein. Abrasive wear of
fiber strands causes detrimental effects to the fiber strands, such
as strand breakage during processing and surface defects in
products such as woven cloth and composites, which increases waste
and manufacturing cost.
[0080] In the fiber forming step, for example, fibers, particularly
glass fibers, contact solid objects such as a metallic gathering
shoe and a traverse or spiral before being wound into a forming
package. In fabric assembly operations, such as knitting or
weaving, the glass fiber strand contacts solid objects such as
portions of the fiber assembly apparatus (e.g. a loom or knitting
device) which can abrade the surfaces of the contacting glass
fibers. Examples of portions of a loom which contact the glass
fibers include air jet accumulators and shuttles. Surface
asperities of these solid objects that have a hardness value
greater than that of the glass fibers can cause abrasive wear of
the glass fibers. For example, many portions of the twist frame,
loom and knitting device are formed from metallic materials such as
steel, which has a Mohs' hardness up to 8.5.sup.12. Abrasive wear
of glass fiber strands from contact with asperities of these solid
objects causes strand breakage during processing and surface
defects in products such as woven cloth and composites, which
increases waste and manufacturing cost.
[0081] To minimize abrasive wear, in one non-limiting embodiment of
the present invention, the particles have a hardness value which
does not exceed, i.e., is less than or equal to, a hardness value
of the glass fiber(s). The hardness values of the particles and
glass fibers can be determined by any conventional hardness
measurement method, such as Vickers or Brinell hardness, but is
preferably determined according to the original Mohs' hardness
scale which indicates the relative scratch resistance of the
surface of a material on a scale of one to ten. The Mohs' hardness
value of glass fibers generally ranges from 4.5 to 6.5, and is
generally 6. R. Weast (Ed.), Handbook of Chemistry and Physics, CRC
Press (1975) at page F-22, which is specifically incorporated by
reference herein. As a result, in one non-limiting embodiment of
the particles, the Mohs' hardness value of the particles ranges
from 0.5 to 6. The Mohs' hardness values of several non-limiting
examples of particles formed from inorganic materials suitable for
use in the present invention are given in Table A below.
4 TABLE A Particle material Mohs' hardness (original scale) boron
nitride 2.sup.13 graphite 0.5-1.sup.14 molybdenum disulfide
1.sup.15 talc 1-1.5.sup.16 mica 2.8-3.2.sup.17 kaolinite
2.0-2.5.sup.18 gypsum 1.6-2.sup.19 calcite (calcium carbonate)
3.sup.20 calcium fluoride 4.sup.21 zinc oxide 4.5.sup.22 aluminum
2.5.sup.23 copper 2.5-3.sup.24 iron 4-5.sup.25 gold 2.5-3.sup.26
nickel 5.sup.27 palladium 4.8.sup.28 platinum 4.3.sup.29 silver
2.5-4.sup.30 zinc sulfide 3.5-4.sup.31 .sup.13K. Ludema, Friction,
Wear, Lubrication, (1996) at page 27, which is hereby incorporated
by reference. .sup.14R. Weast (Ed.), Handbook of Chemistry and
Physics, CRC Press (1975) at page F-22. .sup.15R. Lewis, Sr.,
Hawley's Condensed Chemical Dictionary, (12th Ed. 1993) at page
793, which is hereby incorporated by reference. .sup.16Hawley's
Condensed Chemical Dictionary, (12th Ed. 1993) at page 1113, which
is hereby incorporated by reference. .sup.17Hawley's Condensed
Chemical Dictionary, (12th Ed. 1993) at page 784, which is hereby
incorporated by reference. .sup.18Handbook of Chemistry and Physics
at page F-22. .sup.19Handbook of Chemistry and Physics at page
F-22. .sup.20Friction, Wear, Lubrication at page 27.
.sup.21Friction, Wear, Lubrication at page 27. .sup.22Friction,
Wear, Lubrication at page 27. .sup.23Friction, Wear, Lubrication at
page 27. .sup.24Handbook of Chemistry and Physics at page F-22.
.sup.25Handbook of Chemistry and Physics at page F-22.
.sup.26Handbook of Chemistry and Physics at page F-22.
.sup.27Handbook of Chemistry and Physics at page F-22.
.sup.28Handbook of Chemistry and Physics at page F-22.
.sup.29Handbook of Chemistry and Physics at page F-22.
.sup.30Handbook of Chemistry and Physics at page F-22. .sup.31R.
Weast (Ed.), Handbook of Chemistry and Physics, CRC Press
(71.sup.st Ed. 1990) at page 4-158.
[0082] As mentioned above, the Mohs' hardness scale relates to the
resistance of a material to scratching. The instant invention
therefore further contemplates particles that have a hardness at
their surface that is different from the hardness of the internal
portions of the particle beneath its surface. More specifically,
the surface of the particle can be modified in any manner well
known in the art, including, but not limited to, chemically
changing the particle's surface characteristics using techniques
known in the art such that the surface hardness of the particle is
less than or equal to
[0083] the hardness of the glass fibers while the hardness of the
particle beneath the surface is greater than the hardness of the
glass fibers. As another alternative, a particle can be formed from
a primary material that is coated, clad or encapsulated with one or
more secondary materials to form a composite material that has a
softer surface. Alternatively, a particle can be formed from a
primary material that is coated, clad or encapsulated with a
differing form of the primary material to form a composite material
that has a softer surface.
[0084] In one non-limiting example, an inorganic particle formed
from an inorganic material such as silicon carbide or aluminum
nitride can be provided with a silica, carbonate or nanoclay
coating to form a useful composite particle. In another embodiment,
the inorganic particles can be reacted with a coupling agent having
functionality capable of covalently bonding to the inorganic
particles and functionality capable of crosslinking into the
film-forming material or crosslinkable resin. Such coupling agents
are described in U.S. Pat. No. 5,853,809 at column 7, line 20
through column 8, line 43, which is incorporated herein by
reference. Useful silane coupling agents include glycidyl,
isocyanato, amino or carbamyl functional silane coupling agents. In
another non-limiting example, a silane coupling agent with alkyl
side chains can be reacted with the surface of an inorganic
particle formed from an inorganic oxide to provide a useful
composite particle having a "softer" surface. Other examples
include cladding, encapsulating or coating particles formed from
non-polymeric or polymeric materials with differing non-polymeric
or polymeric materials. A specific non-limiting example of such
composite particles is DUALITE, which is a synthetic polymeric
particle coated with calcium carbonate that is commercially
available from Pierce and Stevens Corporation of Buffalo, N.Y.
[0085] Although not required, in one non-limiting embodiment of the
present invention, the particles are thermally conductive, i.e.,
preferably have a thermal conductivity of at least 0.2 Watts per
meter K, more preferably at least 0.5 Watts per meter K, measured
at a temperature of 300 K. In a non-limiting embodiment, the
particles have a thermal conductivity of at least 1 Watt per meter
K, more preferably at least 5 Watts per meter K, measured at a
temperature of 300 K. In another non-limiting embodiment, the
thermal conductivity of the particles is at least 25 Watts per
meter K, more preferably at least 30 Watts per meter K, and even
more preferably at least 100 Watts per meter K, measured at a
temperature of 300 K. In another non-limiting embodiment, the
thermal conductivity of the particles ranges from 5 to 2000 Watts
per meter K, preferably from 25 to 2000 Watts per meter K, more
preferably ranges from 30 to 2000 Watts per meter K, and most
preferably ranges from 100 to 2000 Watts per meter K, measured at a
temperature of 300 K. As used herein, "thermal conductivity" means
the property of the particle that describes its ability to transfer
heat through itself. See R. Lewis, Sr., Hawley's Condensed Chemical
Dictionary, (12th Ed. 1993) at page 305, which is specifically
incorporated by reference herein.
[0086] The thermal conductivity of a material can be determined by
any method known to one skilled in the art. For example, if the
thermal conductivity of the material to be tested ranges from 0.001
Watts per meter K to 100 Watts per meter K, the thermal
conductivity of the material can be determined using the preferred
guarded hot plate method according to ASTM C-177-85 (which is
specifically incorporated by reference herein) at a temperature of
300 K. If the thermal conductivity of the material to be tested
ranges from 20 Watts per meter K to 1200 Watts per meter K, the
thermal conductivity of the material can be determined using the
guarded hot flux sensor method according to ASTM C-518-91 (which is
specifically incorporated by reference herein). In other words, the
guarded hot plate method is to be used if the thermal conductivity
ranges from 0.001 Watts per meter K to 20 Watts per meter K. If the
thermal conductivity is over 100 Watts per meter K, the guarded hot
flux sensor method is to be used. For ranges from 20 to 100 Watts
per meter K, either method can be used.
[0087] In the guarded hot plate method, a guarded hot plate
apparatus containing a guarded heating unit, two auxiliary heating
plates, two cooling units, edge insulation, a temperature
controlled secondary guard, and a temperature sensor read-out
system is used to test two essentially identical samples. The
samples are placed on either side of the guarded heating unit with
the opposite faces of the specimens in contact with the auxiliary
heating units. The apparatus is then heated to the desired test
temperature and held for a period of time required to achieve
thermal steady state. Once the steady state condition is achieved,
the heat flow (Q) passing through the samples and the temperature
difference (.DELTA.T) across the samples are recorded. The average
thermal conductivity (K.sub.TC) of the samples is then calculated
using the following formula (I):
K.sub.TC=QL/A.multidot..DELTA.T (I)
[0088] wherein L is the average thickness of the samples and A is
the average of the combined area of the samples.
[0089] For products incorporating fibers and fabrics comprising
selected constituents, e.g. the particles, of the forming size of
the present invention, e.g. electronic supports such as printed
circuit boards, it is believed that the materials with higher
thermal conductivity will more quickly dissipate the heat generated
during a drilling operation from the hole area, resulting in
prolonged drill tip life. The thermal conductivity of selected
material in Table A is included in Table B.
[0090] Although not required, in one non-limiting embodiment of the
particles useful in the present invention, the particles are
electrically insulative or have high electrical resistivity, i.e.,
have an electrical resistivity greater than 1000 microohm-cm. Use
of particles having high electrical resistivity in the
reinforcement for conventional printed circuit board applications
as discussed above inhibits loss of electrical signals due to
conduction of electrons through the reinforcement. For specialty
applications, such as circuit boards for microwave, radio frequency
interference and electromagnetic interference applications,
particles having high electrical resistivity are not required. The
electrical resistance of selected materials in Table A is included
in Table B.
5TABLE B Thermal conductiv- Electrical Mohs' ity (W/m Resistance
hardness Inorganic Solid K at (micro ohm- (original Material 300K)
centimeters) scale) boron nitride 200.sup.32 .sup. 1.7 .times.
10.sup.19 33 2.sup.34 boron phosphide 350.sup.35 -- 9.5.sup.36
aluminum phosphide 130.sup.37 -- -- aluminum nitride 200.sup.38
greater than 10.sup.19 39 9.sup.40 gallium nitride 170.sup.41 -- --
gallium phosphide 100.sup.42 silicon carbide 270.sup.43 4 .times.
10.sup.5 to 1 .times. 10.sup.6 44 greater than 9.sup.45 silicon
nitride 30.sup.46 10.sup.19 to 10.sup.20 47 9.sup.48 beryllium
oxide 240.sup.49 -- 9.sup.50 zinc oxide 26 -- 4.5.sup.51 zinc
sulfide 25.sup.52 2.7 .times. 10.sup.5 to 1.2 .times. 10.sup.12 53
3.5-4.sup.54 diamond 2300.sup.55 2.7 .times. 10.sup.8 56 10.sup.57
silicon 84.sup.58 10.0.sup.59 7.sup.60 graphite up to 100.sup.62
0.5-1.sup.63 2000.sup.61 molybdenum 138.sup.64 5.2.sup.65
5.5.sup.66 platinum 69.sup.67 10.6.sup.68 4.3.sup.69 palladium
70.sup.70 10.8.sup.71 4.8.sup.72 tungsten 200.sup.73 5.5.sup.74
7.5.sup.75 nickel 92.sup.76 6.8.sup.77 5.sup.78 aluminum 205.sup.79
4.3.sup.80 2.5.sup.81 chromium 66.sup.82 20.sup.83 9.0.sup.84
copper 398.sup.85 1.7.sup.86 2.5-3.sup.87 gold 297.sup.88
2.2.sup.89 2.5-3.sup.90 iron 74.5.sup.91 9.sup.92 4-5.sup.93 silver
418.sup.94 1.6.sup.95 2.5-4.sup.96 .sup.32G. Slack, "Nonmetallic
Crystals with High Thermal Conductivity, J. Phys. Chem. Solids
(1973) Vol. 34, pg. 322, which is hereby incorporated by reference.
.sup.33A. Weimer (Ed.), Carbide, Nitride and Boride Materials
Synthesis and Processing, (1997) at page 654. .sup.34Friction,
Wear, Lubrication at page 27. .sup.35G. Slack, "Nonmetallic
Crystals with High Thermal Conductivity, J. Phys. Chem. Solids
(1973) Vol. 34, 325, which is hereby incorporated by reference.
.sup.36R. Lewis, Sr., Hawley's Condensed Chemical Dictionary, (12th
Ed. 1993) at page 164, which is hereby incorporated by reference.
.sup.37G. Slack, "Nonmetallic Crystals with High Thermal
Conductivity, J. Phys. Chem. Solids (1973) Vol. 34, 333, which is
hereby incorporated by reference. .sup.38G. Slack, "Nonmetallic
Crystals with High Thermal Conductivity, J. Phys. Chem. Solids
(1973) Vol. 34, 329, which is hereby incorporated by reference.
.sup.39A. Weimer (Ed.), Carbide, Nitride and Boride Materials
Synthesis and Processing, (1997) at page 654. .sup.40Friction,
Wear, Lubrication at page 27. .sup.41G. Slack, "Nonmetallic
Crystals with High Thermal Conductivity, J. Phys. Chem. Solids
(1973) Vol. 34, p. 333 .sup.42G. Slack, "Nonmetallic Crystals with
High Thermal Conductivity, J. Phys. Chem. Solids (1973) Vol. 34, p.
321, which is hereby incorporated by reference.
.sup.43Microelectronics Packaging Handbook at page 36, which is
hereby incorporated by reference. .sup.44A. Weimer (Ed.), Carbide,
Nitride and Boride Materials Synthesis and Processing, (1997) at
page 653, which is hereby incorporated by reference.
.sup.45Friction, Wear, Lubrication at page 27.
.sup.46Microelectronics Packaging Handbook at page 36, which is
hereby incorporated by reference. .sup.47A. Weimer (Ed.), Carbide,
Nitride and Boride Materials Synthesis and Processing, (1997) at
page 654. .sup.48Friction, Wear, Lubrication at page 27.
.sup.49Microelectronics Packaging Handbook at page 905, which is
hereby incorporated by reference. .sup.50Hawley's Condensed
Chemical Dictionary, (12th Ed. 1993) at page 141, which is hereby
incorporated by reference. .sup.51Friction, Wear, Lubrication at
page 27. .sup.52Handbook of Chemistry and Physics, CRC Press (1975)
at pages 12-54. .sup.53Handbook of Chemistry and Physics, CRC Press
(71st Ed. 1990) at pages 12-63, which is hereby incorporated by
reference. .sup.54Handbook of Chemistry and Physics, CRC Press
(71st Ed. 1990) at page 4-158, which is hereby incorporated by
reference. .sup.55Microelectronics Packaging Handbook at page 36.
.sup.56Handbook of Chemistry and Physics, CRC Press (71st Ed. 1990)
at pages 12-63, which is hereby incorporated by reference.
.sup.57Handbook of Chemistry and Physics at page F-22.
.sup.58Microelectronics Packaging Handbook at page 174.
.sup.59Handbook of Chemistry and Physics at page F-166, which is
hereby incorporated by reference. .sup.60Friction, Wear,
Lubrication at page 27. .sup.61G. Slack, "Nonmetallic Crystals with
High Thermal Conductivity, J. Phys. Chem. Solids (1973) Vol. 34,
322, which is hereby incorporated by reference. .sup.62W.
Callister, Materials Science and Engineering An Introduction, (2d
ed. 1991) at page 637, which is hereby incorporated by reference.
.sup.63Handbook of Chemistry and Physics at page F-22.
.sup.64Microelectronics Packaging Handbook at page 174.
.sup.65Microelectronics Packaging Handbook at page 37.
.sup.66According to "Web Elements"
http://www.shef.ac.uk/.about.chem/web-elents/nofr-image-l/hardness
minerals-l.html (February 26,1998). .sup.67Microelectronics
Packaging Handbook at page 174. .sup.68Microelectronics Packaging
Handbook at page 37. .sup.69Handbook of Chemistry and Physics at
page F-22. .sup.70Microelectronics Packaging Handbook at page 37.
.sup.71Microelectronics Packaging Handbook at page 37.
.sup.72Handbook of Chemistry and Physics at page F-22.
.sup.73Microelectronics Packaging Handbook at page 37.
.sup.74Microelectronics Packaging Handbook at page 37.
.sup.75According to "Web Elements"
http://www.shef.ac.uk/.about.chem/web--
elents/nofr-image-l/hardness-minerals-l.html (February 26, 1998).
.sup.76Microelectronics Packaging Handbook at page 174.
.sup.77Microelectronics Packaging Handbook at page 37.
.sup.78Handbook of Chemistry and Physics at page F-22.
.sup.79Microelectronics Packaging Handbook at page 174.
.sup.80Microelectronics Packaging Handbook at page 37.
.sup.81Friction, Wear, Lubrication at page 27.
.sup.82Microelectronics Packaging Handbook at page 37.
.sup.83Microelectronics Packaging Handbook at page 37.
.sup.84Handbook of Chemistry and Physics at page F-22.
.sup.85Microelectronics Packaging Handbook at page 174.
.sup.86Microelectronics Packaging Handbook at page 37.
.sup.87Handbook of Chemistry and Physics, at page F-22.
.sup.88Microelectronics Packaging Handbook at page 174.
.sup.89Microelectronics Packaging Handbook at page 37.
.sup.90Handbook of Chemistry and Physics at page F-22.
.sup.91Microelectronics Packaging Handbook at page 174.
.sup.92Handbook of Chemistry and Physics, CRC Press (1975) at page
D-171, which is hereby incorporated by reference. .sup.93Handbook
of Chemistry and Physics at page F-22. .sup.94Microelectronics
Packaging Handbook at page 174. .sup.95Microelectronics Packaging
Handbook at page 37. .sup.96Handbook of Chemistry and Physics at
page F-22.
[0091] It will be appreciated by one skilled in the art that
particles of the forming size composition of the present invention
can include any combination or mixture of particles discussed
above. More specifically, and without limiting the present
invention, the particles can include any combination of additional
particles made from any of the materials described above. Thus, all
particles do not have to be the same; they can be chemically
different and/or chemically the same but different in configuration
or properties.
[0092] Generally, the particles are present in the forming size
composition in an amount ranging from 1 to 30 weight percent of the
forming size composition on a total solids basis. In one
non-limiting embodiment, the particles range from 1 to 20 weight
percent of the sizing composition on a total solids basis. In
another non-limiting embodiment, the particles range from 1 to 10
weight percent of the sizing composition on a total solids basis.
In other non-limiting embodiments of the present
[0093] invention, the forming size compositions include, but are
not limited to: i) sizings comprising an organic component and
lamellar particles having a thermal conductivity of at least 1 Watt
per meter K at a temperature of 300 K; ii) sizings comprising an
organic component and non-hydratable, lamellar particles; iii)
sizings comprising at least one boron-free lamellar particle having
a thermal conductivity of at least 1 Watt per meter K at a
temperature of 300 K; iv) lamellar particles having a thermal
conductivity of at least 1 Watt per meter K at a temperature of 300
K, i.e., lamellar particles on the fiber; v) alumina-free,
non-hydratable particles having a thermal conductivity of at least
1 Watt per meter K at a temperature of 300 K, i.e., alumina-free,
non-hydratable particles on the fiber, vi) at least one particle
selected from inorganic particles, organic hollow particles and
composite particles, the at least one particle having a Mohs'
hardness value which does not exceed the Mohs' hardness value of at
least one glass fiber, and vii) a plurality of discrete particles
formed from materials selected from non-heat expandable organic
materials, inorganic polymeric materials, non-heat expandable
composite materials and mixtures thereof, the particles having an
average particle size sufficient to allow strand wet out without
application of external heat.
[0094] The coating compositions of the present invention can
further include one or more lubricious materials that are
chemically different from the polymeric materials and softening
agents discussed above to impart desirable processing
characteristics to the fiber strands during weaving. Suitable
lubricious materials can be selected from oils, waxes, greases, and
mixtures of any of the foregoing. Non-limiting examples of wax
materials useful in the present invention include aqueous soluble,
emulsifiable or dispersible wax materials such as vegetable,
animal, mineral, synthetic or petroleum waxes, e.g. paraffin. Oils
useful in the present invention include both natural oils,
semisynthetic oils and synthetic oils.
[0095] The lubricious materials can include waxes and oils having
polar characteristics such as, but not limited to, highly
crystalline waxes having polar characteristics. In one non-limiting
embodiment, the waxes has a melting point above 35.degree. C. and
in another non-limiting embodiment of the present invention, the
waxes have a melting point above 45.degree. C. Such materials are
believed to improve the wet-out and wet-through of polar resins on
fiber strands coated with sizing compositions containing such polar
materials as compared to fiber strands coated with sizing
compositions containing waxes and oils that do not have polar
characteristics. However, it should be appreciated that the effect
such materials have on wet-out and wet-through depends on how much,
if any, of these materials remain on the fibers and/or within the
fiber strands after heat cleaning. Non-limiting examples of
lubricious materials having polar characteristics include esters
formed from reacting (1) a monocarboxlyic acid and (2) a monohydric
alcohol. Preferably,the wax component comprises at least 90 weight
percent of the ester on a total solids basis. Non-limiting examples
of such fatty acid esters useful in the present invention include
cetyl palmitate (such as is available from Stepan Company of
Maywood, N.J. as KESSCO 653 or STEPANTEX 653), cetyl myristate
(also available from Stepan Company as STEPANLUBE 654), cetyl
laurate, octadecyl laurate, octadecyl myristate, octadecyl
palmitate and octadecyl stearate. Other fatty acid ester,
lubricious materials useful in the present invention include, but
are not limited to, trimethylolpropane tripelargonate, natural
spermaceti and triglyceride oils, such as but not limited to
soybean oil, linseed oil, epoxidized soybean oil, and epoxidized
linseed oil.
[0096] The lubricious materials can also include water-soluble
polymeric materials. Non-limiting examples of useful materials
include polyalkylene polyols and polyoxyalkylene polyols, such as
MACOL E-300, which is commercially available from BASF Corporation
of Parsippany, N.J., and CARBOWAX 300 and CARBOWAX 400, which is
commercially available from Union Carbide Corporation of Danbury,
Conn. Another non-limiting example of a useful lubricious material
is POLYOX WSR 301 which is a poly(ethylene oxide) commercially
available from Union Carbide Corporation.
[0097] The coating compositions of the present invention can
additionally include one or more other lubricious materials, such
as non-polar petroleum waxes, in lieu of or in addition to of those
lubricious materials discussed above. Non-limiting examples of
non-polar petroleum waxes include MICHEM.RTM. LUBE 296
microcrystalline wax, POLYMEKON.RTM. SPP-W microcrystalline wax and
PETROLITE 75 microcrystalline wax which are commercially available
from Michelman Inc. of Cincinnati, Ohio and Baker Petrolite,
Polymer Division, of Cumming, Ga., respectively.
[0098] Generally, the amount of wax or other lubricious material
present in the forming size composition of the present invention
ranges from 5 to 50 weight percent of the aqueous sizing
composition on a total solids basis. In one non-limiting
embodiment, the amount of wax or other lubricious material present
in the sizing composition ranges from 20 to 45 weight percent of
the aqueous sizing composition on a total solids basis. In another
non-limiting embodiment, the amount of wax or other lubricious
material present in the sizing composition ranges from 10 to 45
weight percent of the aqueous sizing composition on a total solids
basis.
[0099] The forming size compositions of the present invention can
additionally include one or more emulsifying agents for emulsifying
or dispersing components of the sizing compositions, such as the
particles and/or lubricious materials. Non-limiting examples of
suitable emulsifying agents or surfactants include polyoxyalkylene
block copolymers (such as PLURONICTM F-108
polyoxypropylene-polyoxyethylene copolymer which is commercially
available from BASF Corporation of Parsippany, N.J.; PLURONIC F-108
copolymer is available in Europe under the tradename SYNPERONIC
F-108), ethoxylated alkyl phenols (such as IGEPAL CA-630
ethoxylated octylphenoxyethanol which is commercially available
from GAF Corporation of Wayne, N.J.), polyoxyethylene octylphenyl
glycol ethers (such as TRITON X-100, which is commercially
available from Union Carbide of Danbury, Conn.), ethylene oxide
derivatives of sorbitol esters (such as TMAZ 81 which is
commercially available BASF of Parsippany, N.J. and TWEEN 21 and
which are commercially available from ICI Americas, Inc. of Atlas
Point, Del.), polyoxyethylated vegetable oils (such as ALKAMULS
EL-719, which is commercially available from Rhone-Poulenc/Rhodia
and EMULPHOR EL-719 which is commercially available from GAF
Corp.), ethoxylated alkylphenols (such as MACOL OP-10 SP which is
also commercially available from BASF) and nonylphenol surfactants
(such as MACOL NP-6 and ICONOL NP-6 which are also commercially
available from BASF, and SERMUL EN 668 which is commercially
available from CON BEA, Benelux).
[0100] Generally, the amount of emulsifying agent can range from
0.01 to 25 weight percent of the forming size composition on a
total solids basis. In one non-limiting embodiment, the amount of
emulsifying agent ranges from 0.1 to 10 weight percent of the
forming size composition on a total solids basis.
[0101] The aqueous forming size composition can also comprise one
or more cationic lubricants different from the lubricious materials
discussed earlier. Non-limiting examples of such cationic
lubricants are glass fiber lubricants which include amine salts of
fatty acids (which can, for example, include a fatty acid moiety
having 12 to 22 carbon atoms and/or tertiary amines having alkyl
groups of 1 to 22 atoms attached to the nitrogen atom), alkyl
imidazoline derivatives (such as can be formed by the reaction of
fatty acids with polyalkylene polyamines), acid solubilized fatty
acid amides (for example, saturated or unsaturated fatty acid
amides having acid groups of 4 to 24 carbon atoms such as stearic
amide), acid solubilized polyunsaturated fatty acid amides,
condensates of a fatty acid and polyethylene imine and amide
substituted polyethylene imines, such as EMERY 6717, a partially
amidated polyethylene imine commercially available from Cognis
Corporation of Cincinnati, Ohio and ALUBRASPIN 226 which is
available from BASF Corp. of Parsippany, N.J.
[0102] Non-limiting examples of useful alkyl imidazoline
derivatives are CATION X, which is commercially available from
Rhone Poulenc/Rhodia of Princeton, N.J., and ALUBRASPIN 261, which
is available from BASF Corp. of Parsippany, N.J.
[0103] Although not limiting in the present invention, in one
embodiment the cationic lubricant includes one or more silylated
polyamine polymers. One non-limiting example of a cationic
lubricant is ALUBRASPIN 227 silylated polyamine polymer lubricant,
which is manufactured by BASF Corp. of Parsippany, N.J. and is
disclosed in U.S. Pat. No. 5,354,829.
[0104] Generally the amount of cationic lubricant is no greater
than 15 weight percent of the forming size composition on a total
solids basis. In one non-limiting embodiment, the amount of
cationic lubricant ranges from 0.1 to 10 weight percent of the
forming size composition on a total solids basis. In another
non-limiting embodiment, the amount of cationic lubricant ranges
from 1 to 5 weight percent of the forming size composition on a
total solids basis.
[0105] The forming size composition can further include one or more
surface modifying or coupling agents selected from functional
organo silane, organo titanate and organo zirconate coupling
agents. Such coupling agents typically have dual functionality.
Each metal or silicon atom has attached to it one or more
hydrolyzable groups which can react with the glass surface to
remove hydroxyl groups and one or more groups which, it is
believed, can compatibilize or react with other components in the
forming size composition, such as the N-vinyl amide polymer.
[0106] Non-limiting examples of useful functional organo-silane
coupling agents include gamma-aminopropyltrialkoxysilanes,
gamma-isocyanatopropylt- riethoxysilane, vinyl-trialkoxysilanes,
glycidoxypropyltrialkoxysilanes and ureidopropyltrialkoxysilanes.
Non-limiting examples of useful functional organo-silane coupling
agents include A-187 gamma-glycidoxy-propyltrimethoxysilane, A-174
gamma-methacryloxypropyltri- methoxysilane, A-1100
gamma-aminopropyltriethoxysilane silane coupling agents, A-1108
amino silane coupling agent and A-1160
gamma-ureidopropyltriethoxysilane (each of which is commercially
available from Crompton Corporation of Greenwich, Conn.). The
organo silane coupling agent can be at least partially hydrolyzed
with water prior to application to the fibers, for example at a 1:1
stoichiometric ratio or, if desired, applied in unhydrolyzed form.
The pH of the water can be modified by the addition of an acid or a
base to initiate or speed the hydrolysis of the coupling agent as
is well known in the art. Other examples of useful silane coupling
agents are set forth in K. Loewenstein, The Manufacturing
Technology of Continuous Glass Fibres at page 253 (3d Ed. New York
1983), which is hereby incorporated by reference.
[0107] The amount of coupling agent can range from 0.5 to 25 weight
percent of the forming size composition on a total solids basis. In
one non-limiting embodiment, the amount of coupling agent ranges
from 1 to 10 weight percent of the sizing composition on a total
solids basis. In another non-limiting embodiment, the amount of
coupling agent ranges from 1 to 5 weight percent of the sizing
composition on a total solids basis.
[0108] The aqueous forming size composition can further comprise
one or more non-ionic lubricants different from the lubricious
materials discussed earlier, which are believed to increase tension
in warping. Non-limiting examples of useful non-ionic lubricants
include esters of carboxylic acids and polyhydric alcohols, and
mineral oils.
[0109] Non-limiting examples of useful non-ionic lubricants include
vegetable oils and hydrogenated vegetable oils, such as cottonseed
oil, corn oil and soybean oil; trimethylolpropane triesters;
pentaerythritol tetraesters; derivatives and mixtures thereof.
Useful trimethylolpropane triesters and pentaerythritol tetraesters
are commercially available from Stepan Company. The non-ionic
lubricants are typically solids or liquids at ambient temperature
(about 25.degree. C.).
[0110] One non-limiting non-ionic lubricant is ECLIPSE 102
hydrogenated soybean oil, which is commercially available from
Loders Croklaan of Glen Ellyn, Ill.
[0111] The non-ionic lubricant is generally present in the aqueous
forming size composition in an amount of 0.001 weight percent to
less than 15 weight percent on a total solids basis. In one
non-limiting embodiment, the non-ionic lubricant is present in the
aqueous forming size composition in an amount ranging from 5 to 15
weight percent on a total solids basis.
[0112] The emulsifying agent can also function as an emulsifier for
the non-ionic lubricants, or a second emulsifying agent different
from the emulsifying agent for the wax component can be included in
the aqueous forming size composition. Any of the emulsifying agents
discussed above are also suitable emulsifiers for the non-ionic
lubricant.
[0113] The wax component of the forming size composition can also
include one or more aqueous soluble, emulsifiable or dispersible
waxes different from the ester, which has been described in detail
above. Non-limiting examples of such waxes include vegetable,
animal, mineral, synthetic or petroleum waxes. In one non-limiting
embodiment of the present invention, the wax has a high degree of
crystallinity and is obtained from a paraffinic source, such as a
microcrystalline wax. Other useful microcrystalline waxes are
commercially available from Baker Petrolite, Polymer Division,
Cumming, Georgia and Michelman, Inc. of Cincinnati, Ohio. However,
in one non-limiting embodiment of the invention, the forming size
composition is essentially free of waxes different from the ester.
As used herein, "essentially free of waxes different from the
ester" means the forming size composition comprises 0.1 to 5 weight
percent of the forming size composition on a total solids
basis.
[0114] Fungicides, bactericides and anti-foaming materials can also
be included in the forming size composition. A non-limiting example
of a useful fungicide is methylene-bis-thiocyanate CHEMTREAT
CL-2141, which is commercially available from ChemTreat, Inc. of
Ashland, Va. A non-limiting example of a suitable bactericide is
BIOMET 66 antimicrobial compound, which is commercially available
from M & T Chemicals of Rahway, N.J. Non-limiting examples of
suitable anti-foaming materials are the SAG materials, which are
commercially available from Crompton Corporation of Greenwich,
Conn., and Mazu DF-136, which is commercially available from BASF
Corp. of Parsippany, N.J.
[0115] The amount of fungicide, bactericide or anti-foaming
materials generally ranges from 1.times.10.sup.-4 to 5 weight
percent of the forming size composition on a total solids
basis.
[0116] The forming size composition can further comprise one or
more organic acids in an amount sufficient to provide the aqueous
forming size composition with a pH ranging from 3 to 10. In one
non-limiting embodiment of the present invention, the forming size
composition comprises one or more organic acids in an amount
sufficient to provide the aqueous forming size composition with a
pH ranging from 4 to 8. Non-limiting examples of organic acids
suitable for use in the present invention include mono- and
polycarboxylic acids and/or anhydrides thereof, such as acetic,
citric, formic, propionic, caproic, lactic, benzoic, pyruvic,
oxalic, maleic, fumaric, acrylic, methacrylic acids and mixtures
thereof.
[0117] Water (preferably deionized) is the predominant solvent for
the forming size composition and is present in an amount sufficient
to facilitate application of a generally uniform coating upon the
glass fibers. The weight percentage of solids of such an aqueous
forming size composition can range from 0.5 to 20 weight percent.
In one non-limiting embodiment of the present invention, the weight
percentage of solids ranges from 1 to 10 weight percent. In another
non-limiting embodiment of the present invention, the weight
percentage of solids ranges from 2 to 8 weight percent.
[0118] The aqueous forming size composition can further include one
or more humectants. Non-limiting examples of humectants include
dihydric alcohols, polyhydric alcohols, ureas and mixtures thereof.
Non-limiting examples of polyhydric alcohols include polyalkylene
polyols, polyoxyalkylene polyols and mixtures thereof. Non-limiting
examples of such humectants include polyethylene glycols, such as
MACOL E-300, which is commercially available from BASF Corp. of
Parsippany, N.J. and CARBOWAX products, which are commercially
available from Union Carbide Corp. of Danbury, Conn. Other
humectants include glycerols such as are commercially available
from Sigma Chemical and Dow Chemical USA of Midland, Mich. However,
in one non-limiting embodiment of the invention, the size
composition is essentially free of humectants. As used herein,
"essentially free of humectants" means that the aqueous forming
size composition contains less than 5 weight percent of humectants
based upon the total weight of the composition, and preferably less
than about 3 weight percent.
[0119] Without limiting the present invention, in one embodiment,
the aqueous forming size composition is essentially free of
polyolefin emulsions, such as aqueous emulsions of polyolefins
selected from polyethylene, polypropylene and copolymers of
ethylene and propylene. Such polyolefin emulsions are believed to
be hydrophobic and are believed to adversely affect wet-out in
slashing, particularly under humid conditions or when water-based
slashing sizes are used. A non-limiting example of a high density
polyethylene emulsion is PROTOLUBE HD, which is commercially
available from Sybron Chemicals of Birmingham, N.J. As used herein,
"essentially free of polyolefin emulsions" means that the aqueous
forming size composition contains less than 5 weight percent of
polyolefin emulsions based upon the total weight of the sizing
composition.
[0120] Without limiting the present invention, in one embodiment
the aqueous forming size composition is essentially free of
preservatives selected from organometallic compounds,
formaldehydes, derivatives and mixtures thereof. Non-limiting
examples of such preservatives include emulsified organotin
compounds and formalin. As used herein, "essentially free of
preservatives selected from organometallic compounds,
formaldehydes, derivatives and mixtures thereof" means that the
aqueous forming size composition contains less than 0.01 weight
percent of such preservatives on a total solids basis.
[0121] Without limiting the present invention, in one embodiment
the aqueous forming size composition is essentially free of salts
of polyamino functional polyamide resins, such as are obtained by
the condensation of a polyamine with a difunctional fatty acid.
Such salts of polyamino functional polyamide resins are believed to
increase resistance to heat cleaning, cause darkening or
discoloration the cloth in heat cleaning and produce slashing
problems. Such polyamines can include alkyl amines having 2 to 8
carbon atoms. Such difunctional fatty acids include those obtained
from the dimerization of fatty acids having 8 to 18 carbons atoms.
Non-limiting examples of salts of polyamino functional polyamide
resins include the VERSAMID and GENAMID products, which are
commercially available from Cognis Corp. of Cincinnati, Ohio and
EPICURE 3180 E-75 polyamide resin solution, which is commercially
available from Shell Chemical of Houston, Tex. The phrase
"essentially free of salts of polyamino functional polyamide
resins" means that the aqueous forming size composition comprises
less than 4 weight percent, and more preferably less than 1 weight
percent, of salts of polyamino functional polyamide resins on a
total solids basis.
[0122] As discussed earlier, the heat cleaning operation can remove
portions of the forming size composition from the fibers of a
fabric. In one non-limiting embodiemnt of the present invention, it
is anticipated that at least a portion of the particles as
disclosed herein will remain on the surface of the fibers and/or
within the fiber bundles after heat cleaning so that the particles
can provide protection to the fibers during subsequent processing.
In another non-limiting embodiment of the present invention, it is
anticipated that at least a portion of the particles as disclosed
herein, will remain on the surface of the fibers and/or within the
fiber bundles after heat cleaning and are compatible with a resin
applied the the fabric and facilitate good penetration of the resin
when applied to the fiber strand bundles. In addition, since the
particles thereafter become part of the fiber/resin composite, the
particles can provide additional properties to the composite such
as but not limited to improved drilling properties, desired thermal
conductivity and electrical resistivity, as discussed earler. It is
also anticipated that other selected constituents of the forming
size may also remain on the surface of the fibers and/or within the
fiber bundles after heat cleaning and may provide the additional
properties to the fabric and/or composite as discussed earlier.
[0123] The aqueous forming size composition of the present
invention can be prepared by any suitable method well known to
those of ordinary skill in the art.
[0124] As discussed earlier, the forming size compositions of the
present invention can be applied to any type of fiberizable glass
composition known to those skilled in the art In addition, the
aqueous forming size compositions can be applied to the glass
fibers in a variety of conventional ways, for example, by dipping
the glass fibers in a bath containing the composition, by spraying
the composition upon the glass fibers or by contacting the glass
fibers with an applicator such as a roller or belt applicator. In
one non-limiting embodiment of applying the size composition, the
aqueous forming size composition is applied by a belt or roller
applicator. Non-limiting examples of such applicators and other
suitable applicators are disclosed in Loewenstein at pages 169-177,
which is hereby incorporated by reference.
[0125] The amount of the forming size composition applied to the
glass fibers can vary based upon such factors as the size and
number of glass fibers. For a plurality of glass fibers, the amount
of aqueous forming size composition having 0.5 to 20 weight percent
solids applied to the fibers ranges from 0.1 to 40 weight percent
of the total weight of the glass fibers including the forming size
composition. In one non-limiting embodiment, the amount of aqueous
forming size composition ranges from 1 to 20 weight percent of the
total weight of the glass fibers including the forming size
composition.
[0126] After application of the forming size composition to the
glass fibers, the glass fibers are typically dried, for example air
dried or dried in a conventional or vacuum oven to produce glass
fiber strands having a dried residue of the forming size
composition thereon. Suitable ovens for drying glass fibers are
well known to those skilled in the art. The temperature and time
for drying the glass fibers will depend upon such variables as the
percentage of solids in the forming size composition, components of
the forming size composition and type of glass fiber. A typical,
although non-limiting drying cycle includes heating the fibers to a
temperature range of 104.degree. C. to 149.degree. C. (220.degree.
F. to 300.degree. F.) for 10 to 13 hours. Drying of glass fiber
forming packages, or cakes, is discussed in detail in Loewenstein
at pages 224-230, which is hereby incorporated by reference.
[0127] Although not limiting in the present invention, the amount
of solids of the forming size composition of the present invention
on the fiber strands as measured by loss on ignition (LOI),
typically ranges from 0.01 to 8 weight percent. In one non-limiting
embodiment of the invention, the LOI ranges from 0.2 to 3 weight
percent. As used herein the term "loss on ignition" means the
weight percent of dried coating composition present on the surface
of the fiber strand as determined by the following formula
(II):
LOI=100.times.[(W.sub.dry-W.sub.bare)/W.sub.dry] (II)
[0128] wherein W.sub.dry is the weight of the fiber strand plus the
residue of the coating composition after drying in an oven at
220.degree. F. (104.degree. C.) for 60 minutes and W.sub.bare is
the weight of the bare fiber strand after removal of residue of the
coating composition by heating the fiber strand in an oven at
1150.degree. F. (621.degree. C.) for 20 minutes and cooling to room
temperature in a dessicator.
[0129] Glass fiber strands having the dried forming size
composition of the present invention applied thereto can be used,
for example, as a warp strand and/or weft strand of a woven fabric,
as discussed earlier. In addition, the glass fibers can be twisted
and/or can have applied thereon a secondary treatment or coating
composition. For example, for glass fiber strands used in the
weaving process, a slashing composition is typically applied to the
sized glass fiber during warping or beaming. Such slashing
compositions typically include components such as polyvinyl alcohol
and are well known to those skilled in the art. The slashing
operation is used to protect the warp yarn from abrasion as fill
yarn is inserted between the warp yarns in a weaving operation. As
discussed earlier, the particles of the present invention provide
desired interstitial spacing between the fibers. As a result, the
forming size of the present invention can facilitate penetration of
the fiber strands by the slasing size. However, also as discussed
earlier, the particles included in the forming size of the present
invention can act as lubricants that reduce the abrasive wear on
the warp yarn. As a result, the forming size of the present
invention may reduce or possibly eliminate the need for applying a
slashing size to the warp yarn prior to weaving.
[0130] The secondary treatment or coating composition can also be
an impregnating composition such as are disclosed in Loewenstein at
page 253, which is hereby incorporated by reference, and U.S. Pat.
Nos. 4,762,750 (col. 5, line 58 through col. 15, line 64; col. 17,
lines 16-46; and col. 19, line 28 through col. 26) and 4,762,751,
(col. 6, line 21 through col. 14, line 68 and col. 16, line 49
through col. 25, line 23) which are hereby incorporated by
reference or a Teflon.RTM. polytetrafluoroethylene coating, for
example.
[0131] The glass fiber strands can be further processed by twisting
into a yarn, chopping, combination in parallel to form a bundle or
roving, weaving into a cloth or forming into a chopped or
continuous strand mat, as discussed above. The glass fiber strands
can be twisted by any conventional twisting technique known to
those skilled in the art, for example by using twist frames.
Generally, twist is imparted to the strand by feeding the strand to
a bobbin rotating at a speed which would enable the strand to be
wound onto the bobbin at a faster rate than the rate at which the
strand is supplied to the bobbin. Generally, the strand is threaded
through an eye located on a ring which traverses the length of the
bobbin to impart twist to the strand, typically about 0.5 to about
3 turns per inch.
[0132] Twisted strands and non-twisted strands (sometimes referred
to as zero twist strands) can be used to prepare woven or non-woven
fabrics, knitted or braided products, or reinforcements. A suitable
woven reinforcing fabric can be formed by using any conventional
loom well known to those skilled in the art, such as a shuttle loom
or rapier loom, but preferably is formed using an air jet loom. Air
jet looms are commercially available, for example, from Tsudakoma
of Japan as Model No. 103 and Sulzer Brothers Ltd. of Zurich,
Switzerland as Model Nos. L-5000 or L-5100. See Sulzer Ruti L5000
and L5100 Product Bulletins of Sulzer Ruti Ltd., Switzerland, which
are hereby incorporated by reference. As used herein, "air jet
weaving" means a type of fabric weaving using an air jet loom in
which fill yarn (weft) is inserted into a warp shed formed by the
warp yarn by a blast of compressed air from one or more air jet
nozzles, in a manner well known to those skilled in the art. The
fill yarn is propelled across the width of the fabric, typically 10
to 60 inches (0.254 to 1.524 meters), by the compressed air.
[0133] The compatibility and aerodynamic properties of different
yarns with the air jet weaving process can be determined by the
following method, which will generally be referred to herein as the
"Air Jet Transport Drag Force" Test Method. The Air Jet Transport
Drag Force Test is used to measure the attractive or pulling force
("drag force") exerted upon the yarn as the yarn is pulled into the
air jet nozzle by the force of the air jet. In this method, each
yarn sample is fed at a rate of about 274 meters (about 300 yards)
per minute through a Sulzer Ruti needle air jet nozzle unit Model
No. 044 455 001 which has an internal air jet chamber having a
diameter of 2 millimeters and a nozzle exit tube having a length of
20 centimeters (commercially available from Sulzer Ruti of
Spartanburg, N.C.) at a desired air pressure, typically between
about 172 to about 379 kiloPascals (about 25 to about 55 pounds per
square inch) gauge. A tensiometer is positioned in contact with the
yarn at a position prior to the yarn entering the air jet nozzle.
The tensiometer provides a measurement of the gram force (drag
force) exerted upon the yarn by the air jet as the yarn is pulled
into the air jet nozzle.
[0134] The drag force per unit mass can be used as a basis for
relative comparison of yarn samples. For relative comparison, the
drag force measurements are normalized over a one centimeter length
of yarn. The Gram Mass of a one centimeter length of yarn can be
determined according to the following formula (III):
Gram Mass=(.pi.(d/2).sup.2) (N) (.rho..sub.glass) (1 centimeter
length of yarn) (III)
[0135] where d is the diameter of a single fiber of the yarn
bundle, N is the number of fibers in the yarn bundle and
.rho..sub.glass is the density of the glass at a temperature of
25.degree. C. (2.6 grams per cubic centimeter). Table C lists the
diameters and number of fibers in a yarn for several typical glass
fiber yarn products.
6 TABLE C Fiber Diameter Yarn type (centimeters) Number of Fibers
in Bundle G75 9 .times. 10.sup.-4 400 G150 9 .times. 10.sup.-4 200
E225 7 .times. 10.sup.-4 200 D450 5.72 .times. 10.sup.-4 200 DE75
6.35 .times. 10.sup.-4 800
[0136] For example, the Gram Mass of a one centimeter length of G75
yarn is (.pi.(9.times.10.sup.-4/2).sup.2)(400)(2.6 grams per cubic
centimeter)(1 centimeter length of yarn)=6.62.times.10.sup.-4 gram
mass. For DE75 yarn, the Gram Mass is 6.59.times.10.sup.-4 gram
mass. The relative drag force per unit mass ("Air Jet Transport
Drag Force") is calculated by dividing the drag force measurement
(gram force) determined by the tensiometer by the Gram Mass for the
type of yarn tested. For example, for a sample of G75 yarn, if the
tensiometer measurement of the drag force is 68.5, then the Air Jet
Transport Drag Force is equal to 68.5 divided by
6.62.times.10.sup.-4=103,474 gram force per gram mass of yarn.
[0137] The forming size coated strands can be used in a wide
variety of applications, such as cloth for printed circuit boards
and overwrap reinforcements for optical fiber cables, for
example.
[0138] The present invention will now be illustrated by the
following specific, non-limiting example.
EXAMPLES
[0139] Each of the components in the amounts (weight percent of
total solids) set forth in Tables 1, 2 and 3 were mixed to form
aqueous sizing compositions useful in the present invention.
7 TABLE I Wt. Percent Component on Total Solids Basis Sample
Component 1 2 NATIONAL 1554.sup.97 25.7 23.9 AMAIZO 213.sup.98 26.5
24.7 CT 7000.sup.99 33.1 30.8 TMAZ 81.sup.100 3.8 3.5 MACOL OP-10
SP.sup.101 1.4 1.3 POLARTHERM PT 160.sup.102 0.9 3.0
RELEASECOAT-CONC 25.sup.103 2.0 6.7 ALUBRASPIN 261.sup.104 2.2 2.0
EPICURE 3180 E-75.sup.105 1.0 0.9 MAZU DF 136.sup.106 0.8 0.8
Y-5659.sup.107 2.6 2.4 CL-2141.sup.108 <0.1 <0.1 acetic
acid.sup.109 <0.1 <0.1 est. % solids in sizing 6.7 7.2 LOI
0.99 0.99 .sup.97NATIONAL 1554 low amylose crosslinked potato
starch which is commercially available from National Starch and
Chemical Corp. of Bridgewater, New Jersey. .sup.98AMAIZO 213 high
viscosity, crosslinked starch which is commercially available from
American Maize Company of Hammond, IN. .sup.99CT 7000 soybean oil
which is commercially available from C&T Quincy of Charlotte,
NC. .sup.100TMAZ 81 ethylene oxide derivative of a sorbitol ester
emulsifier which is commercially available from BASF Corp. of
Parsippany, New Jersey. .sup.101MACOL OP-10 SP ethoxylated
alkylphenol which is commercially available from BASF Corp. of
Parsippany, New Jersey. .sup.102POLARTHERM .RTM. PT 160 boron
nitride powder which is commercially available from Advanced
Ceramics Corporation of Lakewood, Ohio. .sup.103ORPAC BORON NITRIDE
RELEASECOAT-CONC 25 boron nitride dispersion which is dispersion of
about 25 weight percent boron nitride particles in water,
commercially available from ZYP Coatings, Inc. of Oak Ridge,
Tennessee. .sup.104ALUBRASPIN 261 cationic alkyl imidazoline
derivative lubricant which is commercially available from BASF
Corp. of Parsippany, New Jersey. .sup.105EPICURE 3180 E-75
polyamide resin solution which is commercially available from Shell
Chemical of Houston, Texas. .sup.106MAZU DF-136 defoamer which is
commercially available from BASF Corp. of Parsippany, New Jersey
.sup.107Y-5659 amino silane coupling agent which is commercially
available from Crompton Corporation of Greenwich, CT.
.sup.108CL-2141 methylene-bis-thiocyanate which is commercially
available from ChemTreat, Inc. of Ashland, Virginia.
.sup.109approximately 17.2 grams of acetic acid in a 10 gallon
batch of size.
[0140]
8 TABLE 2 Wt. Percent Component on Total Solids Basis Sample
Component 3 4 5 6 7 8 NATIONAL 1554 .sup.110 48.5 45.4 45.3 44.8
44.1 39.8 AMAIZO 213 .sup.111 8.8 8.3 8.3 8.2 8.0 7.2 DGS .sup.112
1.2 1.1 1.1 1.1 1.1 1.0 ECLIPSE 102 .sup.113 23.0 21.5 21.5 21.3
21.0 18.9 TWEEN 81 .sup.114 3.3 3.1 3.1 3.0 3.0 2.7 POLARTHERM PT
160 .sup.115 -- -- -- -- 1.2 2.4 CATION X .sup.116 3.2 3.0 3.0 3.0
2.9 2.6 CARBOWAX 300 .sup.117 12.0 11.2 11.2 11.1 10.9 9.8
RELEASECOAT-CONC -- -- -- -- 0.8 1.6 25 .sup.118 CL-2141 .sup.119
<0.1 <0.1 <0.1 <0.1 <0.1 <0.1 RHOPLEX B-85
.sup.120 -- 6.4 -- -- -- -- ROPAQUE HP-1055 .sup.121 -- -- 6.5 --
-- -- ROPAQUE HP-543P .sup.122 -- -- -- 7.5 -- -- ROPAQUE OP-96
.sup.123 -- -- -- -- 7.0 14.0 est. % solids in sizing 6.3 6.7 6.7
6.8 6.9 7.7 .sup.110 NATIONAL 1554 low amylose crosslinked potato
starch which is commercially available from National Starch and
Chemical Corp. of Bridgewater, New Jersey. .sup.111 AMAIZO 213 high
viscosity, crosslinked starch which is commercially available from
American Maize Company of Hammond, Indiana. .sup.112 DGS diethylene
glycol monosterate which is commercially available from Stepan
Company of Maywood, New Jersey. .sup.113 ECLIPSE 102 hydrogenated
soybean oil nonionic lubricant which is commercially available from
Loders Croklaan of Glen Ellyn, Illinois. .sup.114 TWEEN 81 which is
an ethylene oxide derivatives of sorbitol esters, commercially
available from ICI Americas, Inc. of Atlas Point, Delaware.
.sup.115 POLARTHERM .RTM. PT 160 boron nitride powder which is
commercially available from Advanced Ceramics Corporation of
Lakewood, Ohio. .sup.116 CATION X, which is an alkyl imidazoline
derivative that is commercially available from Rhone Poulenc of
Princeton, New Jersey. .sup.117 CARBOWAX 300, which is a
polyethylene glycol that is commercially available from Union
Carbide of Danbury, Connecticut. .sup.118 ORPAC BORON NITRIDE
RELEASECOAT-CONC 25 boron nitride dispersion which is dispersion of
about 25 weight percent boron nitride particles in water
commercially available from ZYP Coatings, Inc. of Oak Ridge,
Tennessee. .sup.119 CL-2141 methylene-bis-thiocyanate which is
commercially available from ChemTreat, Inc. of Ashland, Virginia.
.sup.120 RHOPLEX B-85 noncrosslinking solid acrylic particle
emulsion which is commercially available from Rohm and Haas Company
of Philadelphia, Pennsylvania. .sup.121 See product property sheet
entitled: "ROPAQUE .RTM. HP-1055, Hollow Sphere Pigment for Paper
and Paperboard Coatings" October 1994, available from Rohm and Haas
Company, Philadelphia, Pennsylvania at page 1 which is hereby
incorporated by reference. .sup.122 same as ROPAQUE OP-96;
commercially available from Rohm and Haas Company, Philadelphia,
Pennsylvania. .sup.123 See product technical bulletin entitled:
"Architectural Coatings- ROPAQUE .RTM. OP-96, The All Purpose
Pigment", April 1997 available from Rohm and Haas Company,
Philadelphia, PA at page 1 which is hereby incorporated by
reference.
[0141]
9 TABLE 3 Wt. Percent Component on Total Solids Basis Sample
Component 9 10 11 12 13 14 NATIONAL 1554 .sup.124 23.8 21.8 21.9
21.8 21.6 19.5 AMAIZO 213 .sup.125 24.5 22.5 22.5 22.5 22.2 20.1
KESSCO 653 .sup.126 27.2 25.1 25.1 25.1 24.8 22.4 ECLIPSE 102
.sup.127 11.7 10.7 10.8 10.7 10.6 9.6 TWEEN 81 .sup.128 4.0 3.7 3.7
3.7 3.7 3.3 IGEPAL CA-630 .sup.129 1.4 1.3 1.3 1.4 1.3 1.1
POLARTHERM PT 160 .sup.130 -- -- -- 1.2 2.4 PVP K-30 .sup.131 4.8
4.4 4.4 4.4 4.4 3.9 ALUBRASPIN 227 .sup.132 2.6 2.4 2.4 2.4 2.4 2.1
RELEASECOAT-CONC -- -- -- 0.8 1.6 25 .sup.133 CL-2141 .sup.134
<0.1 <0.1 <0.1 <0.1 <0.1 <0.1 RHOPLEX B-85
.sup.135 -- 8.1 -- -- -- -- ROPAQUE HP-1055 .sup.136 -- -- 7.9 --
-- ROPAQUE HP-543P .sup.137 -- -- -- 8.0 -- -- ROPAQUE OP-96
.sup.138 7.0 14.0 acetic acid .sup.139 <0.1 <0.1 <0.1
<0.1 <0.1 <0.1 est. % solids in sizing 4.9 5.4 5.3 5.3 5.4
6.0 .sup.124 NATIONAL 1554 low amylose crosslinked potato starch
which is commercially available from National Starch and Chemical
Corp. of Bridgewater, New Jersey. .sup.125 AMAIZO 213 high
viscosity, crosslinked starch which is commercially available from
American Maize Company of Hammond, Indiana. .sup.126 KESSCO 653
cetyl palmitate which is commercially available from Stepan Company
of Maywood, New Jersey. .sup.127 ECLIPSE 102 hydrogenated soybean
oil nonionic lubricant which is commercially available from Loders
Croklaan of Glen Ellyn, Illinois. .sup.128 TWEEN 81 which is an
ethylene oxide derivatives of sorbitol esters, commercially
available from ICI Americas, Inc. of Atlas Point, Delaware.
.sup.129 IGEPAL CA-630 ethoxylated octylphenoxyethanol emulsifier
which is commercially available from Rhone Poulenc of Princeton,
New Jersey. .sup.130 POLARTHERM .RTM. PT 160 boron nitride powder
which is commercially available from Advanced Ceramics Corporation
of Lakewood, Ohio. .sup.131 PVP K-30 polyvinyl pyrrolidone which is
commercially available from International Specialty Products
Chemicals of Wayne, New Jersey. .sup.132 ALUBRASPIN 227 cationic
silylated polyamine polymer lubricant which is manufactured by BASF
Corp. of Parsippany, New Jersey. .sup.133 ORPAC BORON NITRIDE
RELEASECOAT-CONC 25 boron nitride dispersion which is dispersion of
about 25 weight percent boron nitride particles in water
commercially available from ZYP Coatings, Inc. of Oak Ridge,
Tennessee. .sup.134 CL-2141 methylene-bis-thiocyanate which is
commercially available from ChemTreat, Inc. of Ashland, Virginia.
.sup.135 RHOPLEX B-85 noncrosslinking solid acrylic particle
emulsion which is commercially available from Rohm and Haas Company
of Philadelphia, Pennsylvania. .sup.136 See product property sheet
entitled: "ROPAQUE .RTM. HP-1055, Hollow Sphere Pigment for Paper
and Paperboard Coatings" October 1994, available from Rohm and Haas
Company, Philadelphia, Pennsylvania at page 1 which is hereby
incorporated by reference. .sup.137 same as ROPAQUE OP-96;
commercially available from Rohm and Haas Company, Philadelphia,
Pennsylvania. .sup.138 See product technical bulletin entitled:
"Architectural Coatings- ROPAQUE .RTM. OP-96, The All Purpose
Pigment", April 1997 available from Rohm and Haas Company,
Philadelphia, PA at page 1 which is hereby incorporated by
reference.
[0142] Samples 1 and 2 in Table 1 were prepared as follows:
[0143] 1. NATIONAL 1554 and AMAIZO 213 were combined with water
(preferably deionized) at a temperature ranging from 10.degree. C.
to 40.degree. C. in a premix slurry tank; the materials were then
mixed until the starch was dispersed; the starch was then cooked in
a cooker, such as a standard jet cooker, at a temperature of
124.degree. C. (255.degree. F.), and then transfered to a main mix
tank for subsequent processing.
[0144] 2. In a seperate vessel, CT 7000, TMAZ 81, MACOL OP-10 SP
and POLARTHERM PT 160 were combined with hot water to melt the
materials; the materials were then mixed in a high shear mixer;
additional hot water was added until there was an inversion; the
materials were then added to the main tank.
[0145] 3. RELEASECOAT-CONC 25 was then added to the main tank.
[0146] 4. In a seperate vessel, ALUBRASPIN 261 was mixed with water
to melt it; the materials were then added to the main mix tank.
[0147] 5. In a seperate vessel, EPICURE 3180-F-75 were combined
with water and about half of the acetic acid; materials were then
added to the tank.
[0148] 6. MAZU DF 136 was then added to the main tank
[0149] 7. In a seperate vessel, Y-5659 was combined with water and
the remaining portion of the acetic acid; the materials were then
added to the main tank.
[0150] 8. CL-2141 was then added to the main tank.
[0151] 9. Water was then added, as required, to dilute to the
required volume.
[0152] Samples 3-6 in Table 2 were prepared as follows:
[0153] 1. NATIONAL 1554 and AMAIZO 213 were combined with water
(preferably deionized) at a temperature ranging from 10.degree. C.
to 40.degree. C. in a premix slurry tank; the materials were then
mixed until the starch was dispersed; the starch was then cooked in
a cooker, such as a standard jet cooker, at a temperature of
124.degree. C. (255.degree. F.), and then transfered to a main mix
tank for subsequent processing.
[0154] 2. In a seperate vessel, ECLIPSE 102 was melted with hot
water; DGS TWEEN 81, and POLARTHERM PT 160 were added and melted,
as required; the materials were then emulsified in a high shear
mixer and added to the main mix tank.
[0155] 3. CATION X was then added to the main tank.
[0156] 4. CARBOWAX 300 was then added to the main tank.
[0157] 5. RELEASECOAT-CONC 25 was then added to the main tank.
[0158] 6. CL-2141 was then added to the main tank.
[0159] 7. RHOPLEX B-85/ROPAQUE HP-1055/ROPAQUE HP-543P were then
added to the main tank.
[0160] 8. Water was then added, as required, to dilute to the
required volume.
[0161] Samples 9 and 12 in Table 3 were prepared as follows:
[0162] 1. NATIONAL 1554 and AMAIZO 213 were combined with water
(preferably deionized) at a temperature ranging from 10.degree. C.
to 40.degree. C. in a premix slurry tank; the materials were then
mixed until the starch was dispersed; the starch was then cooked in
a cooker, such as a standard jet cooker, at a temperature of
124.degree. C. (255.degree. F.), and then transfered to a main mix
tank for subsequent processing.
[0163] 2. In a separate vessel, KESSCO 653 and ECLIPSE 102 were
melted with hot water; TWEEN 81, IGEPAL CA-630, and POLARTHERM PT
160 were added and melted, as required; the materials were then
emulsified in a high shear mixer and added to the main mix
tank.
[0164] 3. PVP K-30 was then added to the main tank.
[0165] 4. In a separate vessel, ALUBRASPIN 227 was mixed with
acetic acid and added to the main mix tank.
[0166] 5. RELEASECOAT-CONC 25 was then added to the main tank.
[0167] 6. CL-2141 was then added to the main tank.
[0168] 7. RHOPLEX B-85/ROPAQUE HP-1055/ROPAQUE HP-543P was then
added to the main tank.
[0169] 8. Water was then added, as required, to dilute to the
required volume.
[0170] Samples 1 and 2 were applied to G75 E-glass fiber strands
that were subsequently dried, twisted and woven into a 7623 style
fabric. The LOI is indicated in Table 1. No testing of the fabric
was conducted.
[0171] Samples 3-6 and 9-12 were applied to DE75 E-glass fiber
strands. Each coated glass fiber strand was twisted at 0.7 turns
per inch to form a yarn and wound onto 2 bobbins in a similar
manner using conventional twisting equipment. Each bobbin of
Samples 3-6 and 9-12 had loss on ignition value as shown in Table
4. Samples 3-6 and 9-12 were tested as discussed below.
[0172] Samples 7 and 8 in Table 2 and Samples 13 and 14 in Table 3
are hypothetical sizing formulations that include both boron
nitride particles and acrylic copolymer particles. No fiber strands
coated with these sizing formulations were produced.
TEST 1
[0173] The yarns of Samples 3-6 and 9-12 were evaluated for
Friction Force by pulling each yarn Sample at a rate of 262 meters
(287 yards) per minute through a pair of conventional electronic
tensiometers and around a stationary stainless steel cylinder with
a 4.445 centimeters (1.75 inches) diameter aligned between the
tensiometers such that the yarn Samples made one complete wrap
around the cylinder. The difference in tension between the
tensiometers (in grams) as set forth in Table 4 below is a measure
of the friction against the metal surface and is intended to be
similar to the frictional forces to which the yarn may be subjected
during weaving operations.
10 TABLE 4 Friction Friction Friction Friction Force Force Force
Force LOI (grams) LOI (grams) LOI (grams) LOI (grams) Samples 3 4 5
6 Bobbin 1 1.33 42.62 1.62 41.87 1.52 37.37 1.53 48.14 Bobbin 2
1.55 37.46 1.34 43.56 1.41 46.11 1.57 48.42 Samples 9 10 11 12
Bobbin 1 1.17 40.41 1.55 47.59 1.62 48.37 1.45 39.77 Bobbin 2 1.10
40.22 1.46 47.49 1.32 42.63 1.37 40.49
[0174] As shown in Table 4, Samples 4-6 and 10-12, which were
coated with starch-oil based sizing compositions containing acrylic
copolymer particles of the present invention, had comparable
friction force to Samples 3 and 9, respectively.
TEST 2
[0175] The compatibility of the DE75 sample yarns with the air jet
weaving process were determined using the "Air Jet Transport Drag
Force" Test Method discussed in detail above.
[0176] Each yarn sample was fed at a rate of 274 meters (300 yards)
per minute through a Sulzer Ruti needle air jet nozzle unit Model
No. 044 455 001 which had an internal air jet chamber having a
diameter of 2 millimeters and a nozzle exit tube having a length of
20 centimeters (commercially available from Sulzer Ruti of
Spartanburg, N.C.) at an air pressure varying from 25 to 55 pounds
per square inch (172 to 379 310 kiloPascals) gauge. A tensiometer
was positioned in contact with the yarn at a position prior to the
yarn entering the air jet nozzle. The tensiometer provided
measurements of the gram force (drag force) exerted upon each yarn
sample by the air jet as the respective yarn sample was pulled into
the air jet nozzle. These values are set forth in Table 5
below.
11 TABLE 5 Samples 3 4 5 6 9 10 11 12 Air Pressure Drag Force
(grams)* 25 psi Bobbin 1 57.68 49.82 52.03 50.87 47.46 49.27 53.98
50.21 Bobbin 2 48.42 51.63 55.43 51.34 50.42 48.97 51.16 51.36 30
psi Bobbin 1 70.90 63.47 62.74 66.11 60.11 63.77 70.45 63.47 Bobbin
2 64.50 68.62 70.61 66.16 63.04 64.51 66.34 67.07 35 psi Bobbin 1
87.97 79.26 79.68 79.44 73.17 76.93 85.37 75.83 Bobbin 2 79.03
80.91 84.22 81.96 76.48 79.01 80.27 81.96 40 psi Bobbin 1 100.74
94.62 90.54 93.92 82.92 91.03 100.49 89.96 Bobbin 2 92.48 96.51
98.85 95.67 86.80 93.04 95.21 94.48 45 psi Bobbin 1 109.79 100.63
103.18 101.95 89.75 98.84 108.24 99.60 Bobbin 2 101.93 102.61
106.08 105.34 95.21 99.98 103.32 103.73 50 psi Bobbin 1 122.13
116.25 110.10 114.60 100.68 110.80 117.20 109.71 Bobbin 2 113.72
114.62 119.93 117.95 107.51 114.74 115.19 113.62 55 psi Bobbin 1
136.54 123.64 127.65 126.27 115.65 123.32 131.04 124.30 Bobbin 2
129.46 128.19 132.51 131.09 118.27 127.21 127.05 126.36 *to convert
the Drag Force (grams) to Air Jet Transport Force (gram force per
gram mass of yarn), divide the Drag Force by 6.69 .times.
10.sup.-4
[0177] As shown in Table 5 above, each of the yarns coated with a
starch-oil based sizing composition that included the acrylic
copolymer particle according to the present invention had a drag
force comparable to that of the corresponding commercially
available starch-oil based sizings.
[0178] From the foregoing, it is expected that glass fiber yarns
coated with an aqueous forming size composition as disclosed herein
provide weaving processing at least comparable to yarn coated with
conventional starch-oil sizings that do not include the particles
as disclosed herein.
[0179] It will be appreciated by those skilled in the art that
changes could be made to the embodiments described above without
departing from the broad inventive concept thereof. It is
understood, therefore, that this invention is not limited to the
particular embodiments disclosed, but it is intended to cover
modifications which are within the spirit and scope of the
invention, as defined by the appended claims.
* * * * *
References