Ex Parte Goulas et al

Patent Trial and Appeal Board

Aug 10, 2017

12513670 (P.T.A.B. Aug. 10, 2017)

United States Patent and Trademark Office
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O.Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
12/513,670 08/05/2009 Catherine Goulas 341200US0PCT 4807
22850 7590 08/14/2017
OBLON, MCCLELLAND, MAIER & NEUSTADT, L.L.P.
1940 DUKE STREET
ALEXANDRIA, VA 22314
EXAMINER
KRINKER, YANA B
ART UNIT PAPER NUMBER
1747
NOTIFICATION DATE DELIVERY MODE
08/14/2017 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
patentdocket @ oblon. com
oblonpat @ oblon. com
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PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE
THE PATENT TRIAL AND APPEAL BOARD
Ex parte CATHERINE GOULAS,1
Remi Jacques, and Gilles Querel
Appeal 2016-0018132
Application 12/513,670
Technology Center 1700
Before: MARKNAGUMO, JAMES C. HOUSEL, and GEORGE C. BEST,
Administrative Patent Judges.
NAGUMO, Administrative Patent Judge.
DECISION ON APPEAL
Catherine Goulas, Remi Jacques, and Gilles Querel (“Goulas”) timely
appeal under 35 U.S.C. § 134(a) from the Final Rejection3 of all pending
claims 1 and 3—26. We have jurisdiction. 35 U.S.C. § 6. Because we
reverse the rejection of claims 1, 3—16, and 22—26, and affirm the rejection
of claims 17—21, we affirm-in-part.
1 The real party in interest is identified as Eurokera. (Appeal Brief,
filed 1 June 2015 (“Br”), 2.)
2 Heard 8 August 2017. The Official Transcript will be made of record in
due course.
3 Office Action mailed 2 January 2015 (“Final Rejection”; cited as “FR”).
Appeal 2016-001813
Application 12/513,670
OPINION
A. Introduction4
The subject matter on appeal relates to processes of making glass-
ceramic precursor plates (independent claim 1), the resulting glass-ceramic
precursor plates (independent claims 15 and 19), and glass-ceramic plates
(independent claims 17 and 21) prepared from the precursor plates.
According to the Specification, glass-ceramics are characterized by very low
linear thermal expansion coefficients, generally less than 15 x 10 7 K_1
(Spec. 1, 11. 12—13), and are useful as, e.g., cooktops or fire-resistant plates
(id. at 11. 20-22).
The ’670 Specification teaches that “[gjlass-ceramics are materials
rich in silica that comprise at least one crystalline phase.” (Spec. 1,11. 8—9.)
Glass-ceramics are made by first preparing a precursor (or “mother”) glass,
and then transforming the precursor glass by a ceramization heat treatment
to yield the ultimate glass-ceramic article. (Id. at 11. 9—10.) An important
family of glass-ceramics is said to comprise SiC>2 (silica), AI2O3 (alumina)
and Li20 (lithium oxide), which, upon ceramization, results in P-eucryptite
(LiAlSiCN), P-spudomene (tetragonal LiAl(Si03)2), or P-quartz (SiC>2, also
known as “high quartz”) crystals. (Spec., 1, 11. 15—18; see also Siebers,5
4 Application 12/513,670, Float process for a glass-ceramic,
filed 5 August 2009, as the national stage under 35 U.S.C. § 371 of
PCT/FR07/52299, filed 5 November 2007, claiming the benefit of an
application filed in France on 7 November 2006. We refer to the
“’670 Specification,” which we cite as “Spec.”
5 Siebers; full cite infra at n.10.
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Application 12/513,670
Abstract.) Thus, glass-ceramics are, in part, crystalline, and the precursor
glass must, at some point, crystallize in part to form glass-ceramics.
Such flat glass items can be made by a variety of methods, including
rolling, drawing, casting, and floating, of which floating is widely used
because high surface-quality can be obtained. (Siebers 1 [0004]—[0005].) In
a float glass process, molten glass is prepared by melting the ingredients.
The molten glass is then “fined” or “refined” to remove dissolved gases
which can otherwise result in bubbles. As a refining agent, tin oxide (Sn02)
is preferred as a less toxic alternative to materials such as arsenic oxide
(AS2O3) or antimony oxide (Sb2C>3). (Spec. 6,11. 16—24; see also
Siebers 2 [0042].) The molten glass is then poured onto a bath of molten
metal, generally tin, on which a continuous ribbon of glass is formed,
shaped, “progressively cooled and extracted using extractor rolls which
convey it into an annealing furnace called a lehr.” (Spec. 2,11. 23—28.) The
resulting precursor glass is not yet a glass-ceramic, but, in the words of
the ’670 Specification, “should be converted to a glass-ceramic in an
additional step well known to those skilled in the art.” {Id. at 12,11. 9-11.)
More specifically, the precursor may be converted to a glass-ceramic by
heating to a nucleation temperature range, and then heating to a ceramization
hold temperature, followed by rapid cooling to ambient temperature.
{Id. at 11. 21—32.)
As indicated in the ’670 Specification (Spec. 7—10), a number of
components can be added for various purposes, including TiC>2 and ZrC>2
{id. at 7, Table), which are said to be nucleating agents for P-quartz
crystallization (Siebers 2 [0035]).
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Application 12/513,670
The glass-ceramics—more precisely, the glass-ceramic precursor
compositions—are said to have a high tendency to devitrify, i.e., to
crystallize in part, forming crystalline deposits, during the float glass
process. (Spec. 1,11. 23—25.) Indeed, the Specification states that when
glass-ceramic precursor glass is processed under conventional float glass
processing conditions for soda-lime-silica glass, “devitrification [i.e.,
crystallization] never fails to occur, especially in the zone where the glass is
poured onto the metal float bath.” {Id. at 2,11. 15—21.) The resulting
crystalline deposits may damage the surfaces of rolls that shape or move the
nascent plates in the float glass forming machinery. {Id. at 1,11. 23—30.)
Such rolls are said to need periodic regrinding, as often as every two to three
days. The machinery needs to be designed for ready access to the rolls, and
the expense and down-time for maintenance are said to be significant.
{Id. at 1,1. 30, to 2,1. 7.)
Prior art attempts to address these issues are said to be in need of
improvement. {Id. at 2—3.)
The ’670 Specification reveals that a conventional float glass
installation can be used to prepare ceramic-glass precursor plates provided
that two conditions are met. First, the glass must be poured at a temperature
above its devitrification temperature. Second, the cooling rate during a
specified portion of the float phase must be within a specified range—
specifically, between the temperature, TKGmax, corresponding to the
temperature at which crystal growth rate is maximal, and the temperature,
Tueg, corresponding to the temperature at which crystal growth rate is less
than 1 pm/min. These conditions can be illustrated with the aid of the plot
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Application 12/513,670
of crystal growth rate as a function of float glass temperature provided by
Lautenschlaeger,6 Figure 2, reproduced below (annotations added).
©FQfWtft Rat©
(Figure 2 shows crystal growth rate (abscissa) vs. temperature (ordinate)}
At thermal equilibrium, crystals do not form above the liquidus, also
known as the devitrification onset temperature (about 1250°C in this
Figure). As the temperature of the floating glass decreases, the crystal
growth rate, KG, increases to a maximum at temperature TKGmax (here,
about 1100°C). As the temperature of the floating glass continues to
6 Lautenschlaeger, full cite infra at n. 11.
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Application 12/513,670
decrease, the crystal growth rate decreases to zero at temperature Tueg (here,
about 900°C).
The Specification emphasizes that according the process of the
invention, “no devitrification takes place.” The temperature corresponding
to the temperature of maximal crystal growth rate can be determined by
cooling a hot melt of a particular composition to a temperature T, observing
a holding time t, and then cooling the composition rapidly. {Id. at 4,11. 9—
15.) The size of the crystals formed can be determined by optical
microscopy, and a series of measurements at various T and t will provide the
devitrification onset temperature and the devitrification rate. {Id. at 11. lb-
22.) The Specification teaches that these data may also be obtained by
differential scanning calorimetry (DSC). {Id. at 11. 18—20.)
The ’670 Specification teaches that the temperature of the metal bath
in a float process for an ordinary soda-lime-silica glass is about 1000°C,
which is well below the devitrification temperature of glass-ceramic
precursor compositions. {Id. at 5,11. 6—7.) Accordingly, the Specification
teaches, “in the context of the invention, it is generally necessary for the
molten metal to be above 1150°C, even above 1200°C, and even
above 1250°C, on the surface at the point of casting.” {Id. at 5,11. 7—11.)
The Specification refers to the point at which the crystal growth rate is
a maximum as “tl,” and to the point at which crystal growth rate decreases
to less than 1 pm/m in as “t2,” which is later than tl. Because, in the claimed
process, there is no crystal growth, the temperatures corresponding to these
points are referred to as “theoretical temperatures.” {Id. at 4,11. 2 4.)
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Application 12/513,670
Again, the first condition of the claimed process is that the glass be
poured onto the molten tin at a temperature above the devitrification onset
temperature. The second condition is that the cooling rate during the time
between tl, when the theoretical crystal growth rate is largest, and t2, when
the theoretical crystal growth rate effectively becomes 0, is at
least 18 °C/min and less than 48 °C/min.
Claim 1 is representative and reads:
A process for manufacturing a flat ribbon of precursor glass
for a glass-ceramic, comprising
the continuous floating of the molten glass on a bath of
molten metal in a float chamber,
said glass being poured in the molten state at a
temperature above its devitrification onset temperature
onto the molten metal upstream of the chamber,
said glass progressively forming a ribbon that runs along
said metal bath,
the cooling rate of the glass being
at least 18° C/min and less than 48° C/min between,
on the one hand, the moment tl
when the glass is at the theoretical temperature for
which the devitrification rate is a maximum and,
on the other hand, the later moment t2
when the glass is at the theoretical temperature at
which the devitrification crystal growth rate
becomes less than 1 micron per minute.
(Claims App., Br. 21 (indentation, paragraphing,7 and emphasis added).)
7 In compliance with 37 C.F.R. §1.75(i) (2014): “Where a claim sets forth a
plurality of elements or steps, each element or step of the claim should be
separated by a line indentation.”
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Application 12/513,670
The Examiner maintains the following grounds of rejection:8,9
A. Claims 1, 3—7, 12, 14, 22, 24, and 25 stand rejected under
35 U.S.C. § 103(a) in view of Siebers10 and
Lautenschlaeger.11
A1. Claims 9, 10, and 2612 stand rejected under
35 U.S.C. § 103(a) in view of Siebers, Lautenschlaeger,
and Cooper.13
A2. Claim 8 stands rejected under 35 U.S.C. § 103(a) in view of
the combined teachings of Siebers, Lautenschlaeger, and
Arbab.14
A3. Claims 11 and 13 stand rejected under 35 U.S.C. § 103(a) in
view of Siebers, Lautenschlaeger, and Mouly.15
8 Examiner’s Answer mailed 31 August 2015 (“Ans.”).
9 Because this application was filed before the 16 March 2013, effective
date of the America Invents Act, we refer to the pre-AIA version of the
statute.
10 Lriedrich Siebers et al., Flat float glass, U.S. Patent Application]
Publication 2002/0023463 Al(2002) [cited at Spec 3,1. 10; 9,1. 7] [issued as
U.S. Patent No. 6,846,760 on 25 January 2005].
11 Gerhard Lautenschlaeger et al., Method of making a float glass convertible
into a glass ceramic and float glass made thereby, U.S. Patent Application
Publication 2007/0015653 Al (18 January 2007), based on an application
filed 13 July 2006, [issued as U.S. Patent No. 8,015,842 on 13 September
2011],
12 Claim 26 is not cited in the heading of this rejection, but is discussed in
detail in the Pinal Rejection (PR 7). The issue is moot in this appeal because
Goulas does not contest separately the rejection of claims 9 and 10, with
which claim 26 was rejected.
13 Reid Pranklin Cooper and Glen Bennett Cook, U.S. Patent 6,065,309
(2000).
14 Mehran Arbab et al., U.S. Patent Application Publication
2003/0037569 Al (2003).
15 Raymond J. Mouly, U.S. Patent No. 4,305,745 (1981).
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Application 12/513,670
B. Claims 15—21 and 23 stand rejected under 35 U.S.C. § 103(a)
in view of Siebers ’639.16
B. Discussion
The Board’s findings of fact throughout this Opinion are supported by
a preponderance of the evidence of record.
Rejections A—A3 [Processes], based on Siebers and Lautenschlaeger
The Examiner finds that Siebers discloses a float glass process for
making a flat ribbon of precursor glass in which the molten glass is poured
at a temperature above the devitrification onset temperature on to a bath of
molten metal. (FR 4.) The Examiner finds further that Siebert does not
disclose the specific cooling rate of the glass required by claim 1. {Id. at
1. 14.) The Examiner finds that “Lautenschlaeger teaches that to produce
good quality glass a cooling rate of about 20 to under 30 C/min is applied
over a large temperature range of about 200 C from about 1150 C.” (Id. 15—
17 (citing Lautenschlaeger [0004]).) Because “the temperature range
disclosed by Lautenschlaeger is so expansive,” the Examiner “interpret[s]
that tl and t2 fall within the temperature range.” (Id.) Accordingly, the
Examiner concludes that the process covered by claim 1 would have been
obvious.
Goulas urges that the Examiner erred by selectively choosing
teachings of Lautenschlaeger in paragraph [0004] while ignoring teachings
that “there are some problems overall with the way the art made float glass.”
16 Friedrich Siebers et al., Lithium-aluminosilicate flat float glass, U.S.
Patent Application Publication 2005/0250639 Al (2005).
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Application 12/513,670
(Br. 5,11. 10-13 (citing Lautenschlaeger [0012]).) Moreover, Goulas urges,
“other than the overlapping with 18 to less than 48 in the claims, the
reversible error is that there is no teaching in Lautenschlaeger that provides
any basis to apply this cooling rate between the specific two points
(moments) defined in the claims.” {Id.at 11. 17—20.)
Lautenschlaeger paragraph [0004] reads in full:
To produce good quality glass the temperature of the glass
sheet is reduced with a relatively constant and comparatively
small cooling rate of about 20 to under 30° C. min-1 over a
large temperature range of about 200° C. from
about 1150° C. to 900° C. A careful temperature control in
this temperature range is indispensable. This careful cooling
process is required to minimize thickness variations and the
fine waviness.
(Lautenschlaeger 1 [0004]; emphasis added.)
We do not find Lautenschlaeger paragraph [0012] particularly
relevant to the present discussion, as it appears to be directed to the prior art
DE 100 17 1701 C2 described in preceding paragraph [0011] as relating to a
crystallizable glass that may be drawn to a thickness under the equilibrium
thickness. However, paragraph [0005], which follows paragraph [0004],
makes clear that the description in paragraph [0004] concerns conventional
float glass methods with conventional glasses. Moreover, paragraph [0005]
states unequivocally, in most relevant parts,
When this process is performed with crystallizable glass
compositions, one usually obtains results, which are not
sufficient to satisfy the elevated requirements. In the
temperature range, in which the glass sheet is processed with
a comparatively small cooling rate for the purpose of
drawing the glass sheet, crystallization is already occurring,
so that the later ceramicizing of the glass, i.e. its conversion
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Application 12/513,670
into a glass ceramic, ... is negatively influenced by the
crystals formed during the drawing of the glass sheet in an
undesirable manner.
(Lautenschlaeger 1 [0005]; emphasis added.) Thus, Lautenschlaeger teaches
away from using the prior art “relatively constant and comparatively small
cooling rate of about 20 to under 30° C. min-1 over a large temperature
range of about 200° C. from about 1150° C. to 900° C” for glass-float
processing of crystallizable glass compositions, i.e., of glass-ceramic
precursor compositions.
Accordingly, the Examiner’s argument (Ans. 3 (“Examiner’s
Response C,” etc.)), that the Examiner is relying, not on Lautenschlaeger’s
invention, but on Lautenschlaeger’s description of a prior art process, is
without merit. Although the Examiner is correct that a reference is available
for all of its teachings, it is still necessary to establish a basis for applying
any given teaching. Here, the Examiner has not provided a credible
explanation of why the teachings of Lautenschlaeger paragraph [0004],
which are directed to float glass processing of conventional glasses, would
have been applied to float glass processing of crystallizable glass
compositions, with a reasonable expectation of suppressing devitrification,
i.e., of obtaining solidification without crystallization.
The Examiner makes no findings regarding the further limitations of
the dependent claims and the further teachings of the additional references in
Rejections Al—A3 that cure the defects of Rejection A.
Rejections A—A3 are reversed.
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Rejection B [Products], based on Siebers ’639
Independent claims 15 and 17
The Specification discloses that the claimed process results in a
distinctive profile of SnCE concentration at and near the surface, which is
reflected in increased surface strength of the ultimate glass-ceramics.
(Spec. 6-8.)
Claim 15 reads:
A glass-ceramic precursor glass plate that is
free of crystals and which
comprises SnCE,
the SnC>2 concentration locally reaching a
concentration of at least 5 % by weight within a
thickness of 150 nm from the surface of a main face.
(Claims App., Br. 23.) Claims 16 and 23 depend from claim 15.
The Examiner finds that Siebers ’639 teaches a glass plate meeting the
compositional requirements of claims 15—18 and 23. The examiner finds
further that Siebers ’639 teaches glass compositions with 0.1 to 2.0 wt%
SnC>2. The Examiner determines that the overlap is significant when
compared to the 0.1 to 0.5 wt% disclosed in the ’670 Specification as
leading to the required concentration profile. Accordingly, the Examiner
concludes that the further limitation that the SnC>2 concentration have a
certain local profile within 150 nm of the surface would have been obvious.
(FR 10, last para.)
A difficulty with these findings of fact and conclusions of law, as
Goulas points out (Br. 19-20), is that independent claim 15 is drawn to a
glass-ceramic precursor plate. However, the inventive glass plates described
by Siebers ’639, although having high thermal stability and being capable of
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Application 12/513,670
being chemically and thermally tempered (Siebers ’639 1 [0001]), are not
crystallizable.
In the words of Siebers ’639,
While the glass surface is being formed and the glass is
being transported in the float bath, interactions between glass
melt, float atmosphere and the Sn bath can lead to disruptive
surface defects. If the glass contains more than 2% by
weight of Ti02 + ZrCE, nuclei may form in the glass surface
in contact with the Sn bath, and beta-quartz solid solutions
with a size of up to a few 100 pm may crystallize at these
nuclei, thereby producing disruptive surface crystallization.
In the flat float glass according to the invention, which can
be chemically and thermally tempered, the formation of these
undesirable surface crystals during the float process is
avoided by restricting the nucleating agents which are
customary for the production of glass-ceramics
to ITi02 + /r()2 < 2% by weight. Therefore, the flat float
glasses according to the invention are more resistant to
devitrification but can no longer be converted into glass-
ceramics.
(Siebers ’639 3 [0044] (emphasis added).)
Paragraph [0044] shows that the Examiner’s finding that Siebers ’639
teaches a glass plate that is free of crystals is true—such plates comprise less
than 2 wt% nucleating agents TiCE + ZrCE. But that paragraph also teaches
that such plates cannot be converted to glass-ceramics. The Examiner’s
finding that Siebers ’639 teaches glass precursor plates that are free of
crystals, as required by claim 15, is not supported by substantial evidence.
We therefore reverse the rejection of claims 15, 16, and 23.
Independent claim 17 stands differently. The preamble to claim 17
reads, “[a] glass-ceramic plate containing SnCE,” but the remainder of the
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claim is otherwise worded identically to claim 15. Claim 18 depends from
claim 17.
Siebers ’639 teaches in paragraph [0044] that float glasses that
comprise more than 2 wt% nucleating agents TiCC + ZrCC are not free of
crystals. Goulas has not directed our attention to any credible evidence of
record persons having ordinary skill in the art would have considered such
glasses could not be transformed to glass-ceramics by conventional glass-
ceramic transforming processes. That such glasses are not the subject of the
invention disclosed by Siebers ’639, and that Siebers ’639 disparages them,
are irrelevant to the recognition that such glasses would be precursors to
glass-ceramics. Goulas does not present arguments for the separate
patentability of claim 18.
We therefore affirm the rejection of claims 17 and 18.
Independent claims 19 and 21
The Specification discloses that colorants, e.g., V2O5 (said to give a
black appearance in reflection, with low transmission in the visible, and high
IR transmission in the high infrared, hence aesthetically pleasing as well as
useful for cooktops: (Spec. 10,1. 6—18)) age much less rapidly than flat
glass-ceramic plates produced by rolling {id. at 11,11. 1—9).
Independent claim 19 reads:
A glass-ceramic precursor glass plate containing
a multivalent colorant having,
uniformly over at least one main face of said plate,
a more reduced state on the surface than in the core,
said main face having an area of at least 100 cm2.
(Claims App., Br. 24.) Claim 20 depends from claim 19.
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The preamble to independent claim 21 reads, “[a] glass-ceramic plate
containing,” but claim 21 is otherwise worded identically to claim 19.
Regarding claims 19 and 21, the Examiner finds that Siebers ’639
teaches glass plates comprising a multivalent colorant as well as glass plates
having a main face area of 100 cm2. (FR 11, 1st para.) Accordingly, the
Examiner holds that the subject matter of claims 19 and 21 would have been
obvious. {Id., second paragraph.)
Although, as discussed supra, with respect to claim 17, Siebers ’639
does not describe glass-ceramic precursors that are free of crystals, claim 19
contains no such limitation. Patentability may not be established based on
limitations that are neither express nor implicit in a claim. In re Self, 671
F.2d 1344, 1348 (CCPA 1982) (“Many of appellant’s arguments fail from
the outset because . . . they are not based on limitations appearing in the
claims.”) As discussed supra, Goulas has not explained why the routineer
would have expected that the counter-example compositions comprising
more than 2% by weight of nucleating agents TiCE + ZrCE would not be
convertible to glass-ceramics. Moreover, Goulas does not raise distinct
arguments for the patentability of claims 19 and 21 despite the differences in
limitations from claims 15 and 17. Accordingly, on the present record, we
are not persuaded of harmful error in the rejections of claims 19—21.
The rejection of claims 19—21 is affirmed.
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C. Order
It is ORDERED that the rejection of claims 1, 3—16, and 22—26 is
reversed.
It is ORDERED that the rejection of claims 17—21 is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).
AFFIRMED-IN-PART
16