Heat treatable coated article with diamond-like carbon (dlc) coating

(54) Title: HEAT-TREATED COATED ARTICLE WITH DIAMOND CARBON COATING (DLC) (30) Unionist Priority: 02/09/2003 us 10 / 652,858 (71) Depositor (s): Guardian Industries Corp. (US) (72) Inventor (s): Vijayen s. Veerasamy (74) Attorney: Dannemann, Siemsen, Bigler & Ipanema Moreira (86) International Request: PCTUS2004 / 027H3de20 / 08/2004 (87) International Publication: wo 2005/021454 of 10/03/2005 (57) Summary: TREATED COVERED ARTICLE WITH HEAT WITH DIAMOND TYPE CARBON COATING (DLC). The present invention relates to a method of manufacturing a coated article (e.g., a window unit) and corresponding coated article are provided. A layer of or including diamond-like carbon (DLC) is formed on a glass substrate, preferably on at least one barrier layer. Then, a protective layer is formed on the substrate over the layer containing DLC. During the heat treatment (HT), the protective layer prevents the layer containing DLC ​​from burning. Then, the resulting coated glass substrate can be used as desired, it has been heat treated and including the layer containing protective DLC. The protective layer can be removed after HT.

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Descriptive Report of the Invention Patent for HEAT-TREATED COATED ARTICLE WITH DIAMOND CARBON COATING (DLC).

The present invention relates to a method of manufacturing a coated article to be used in a window unit or any other suitable application. For example, certain embodiments of the present invention relate to a method of manufacturing a window unit (for example, a vehicle window such as a windshield, rear window, sunroof or rear view mirror or IG window unit) including a heat treatment step of a glass substrate coated with at least one layer comprising a diamond-like carbon (DLC). Other embodiments of the present invention relate to such a coated article that can be used in a window application, or any other suitable application. Background of the Invention

Vehicle windows (for example, windshields, rear windows, sunroofs or rear-view mirrors) are known in the art. For example, vehicle windshields typically include a pair of laminated arched glass substrates along with a polymer interlayer such as a polyvinyl butyral (PVB). It is known that one of the two glass substrates can have a coating (for example, coating with little E) on it for solar control purposes such as IR reflecting and / or UV radiation, so that the interior of the vehicle can be more comfortable in certain climatic conditions. Conventional vehicle windscreens are made as follows. First and second flat glass substrates are provided, one of them optionally having a low E coating deposited on it. The pair of glass substrates is washed and joined (ie, stacked on top of each other), and then while joined they are arched with heat together in the desired windshield shape at high temperature (s) (for example, 8 minutes at about 600-625 ° C). The two arched glass substrates are then laminated together through the polymer interlayer to form the vehicle's windshield.

Glass insulating (IG) window units are also. ··. ·· · • ··· * · ··· '· · known in the art. Conventional GI window units include at least first and second glass substrates (one of which may have a solar control coating on its interior surface) that are coupled to each other through at least one (seal) or spacer (es) ).

The resulting gap or gap between the glass substrates may or may not be filled with gas and / or evacuated to a low pressure in different cases. However, many IG units need to be tempered. Thermal tempering of the glass substrates for such IG units typically requires heating the glass substrates to temperature (s) of at least about 600 ° C for a sufficient period of time to allow for thermal tempering.

Other types of coated articles also require heat treatment (HT) (for example, quenching, heat bending and / or heat reinforcement) in certain applications. For example, and without limitation, glass shower doors, glass table tops and the like require HT in certain cases.

Diamond-type carbon (DLC) is sometimes known for its scratch-resistant properties. For example, different types of DLC are discussed in the following US Patents: 6,303,226;

6.303.225; 6.261.693; 6.338.901; 6.312.808; 6.280.834; 6.284.377;

6,335,086; 5,858,477; 5,635,245; 5,888,593; 5,135,808; 5,900,342 and 5,470,661, all of which are incorporated by reference.

It would sometimes be desirable to provide a window unit or other glass article with a protective coating including DLC ​​in order to protect it from scratches and the like. Unfortunately, DLC tends to oxidize and burn at temperatures from approximately 380 to 400 ° C, as heat treatment is typically conducted in an atmosphere including oxygen. Thus, it will be understood that DLC as a protective coating cannot withstand heat treatments (HT) at the extremely high temperatures described above which are often required in the manufacture of vehicle windows, IG window units, glass table tops and / or similar.

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Thus, those skilled in the art will understand that there is a need in the art for a method of providing heat-treated (HT) coated articles with a protective coating (one or more layers) comprising DLC. The need for corresponding coated articles, both heat treated and pre-HT, also exists. Brief Summary of Examples of the Invention

In certain exemplary embodiments of the present invention, a method of manufacturing a coated article (for example, window units such as for a vehicle, building or the like) is provided including heat treatment (HT), where the coated article includes a coating (one or more layers) comprising diamond-type carbon (DLC).

In certain exemplary embodiments, a method of manufacturing a coated article is provided by: (a) providing at least one barrier layer supported by a glass substrate, (b) coating a glass substrate with a layer comprising DLC ​​on at least the barrier layer, then (c) forming a protective layer of sacrifice on the glass substrate on the DLC and (d) heat treatment of the article coated with the DLC and the sacrificial protective layer on it preventing the majority of the DLC from burning during the heat treatment. Following the heat treatment (HT), the sacrificial protection layer can be removed. The resulting heat-treated coated article can be used in the context of, for example, and without limitation, vehicle windows, architectural windows, insulating glass (IG) window units, shower doors, glass table tops and / or similar.

In certain exemplary embodiments of the present invention, the sacrificial protection layer may comprise zirconium nitride.

In other exemplary embodiments of the present invention, the sacrificial protection layer may comprise chromium nitride.

In certain exemplary embodiments of the present invention, a method of making a heat-treated coated article is provided, the method comprising: providing a glass substrate; formation of at least one layer comprising diamond-type carbon (DLC) on the glass substrate; forming a protective layer comprising a zirconium and / or chromium nitride on the glass substrate on at least the layer comprising DLC; heat treatment of the glass substrate with the layer comprising DLC ​​and the protective layer comprising zirconium nitride and / or chromium on it so that during heat treatment the protective layer prevents significant burning of the layer comprising DLC; and removing at least part of the protective layer comprising zirconium nitride and / or chromium after said heat treatment.

In other exemplary embodiments of the present invention, a coated article including a coating supported by a glass substrate is provided, the coating comprising: at least one barrier layer supported by the glass substrate; a layer comprising diamond-like carbon (DLC) on the glass substrate on at least the barrier layer; and a layer comprising a zirconium and / or chromium nitride on the glass substrate on at least the layer comprising DLC.

Brief Description of Drawings

Figure 1 is a cross-sectional view of the coated article, before heat treatment, according to an exemplary embodiment of the present invention.

Figures 2 (a) -2 (c) are seen in cross-section illustrating certain steps carried out in the manufacture of a coated article according to an exemplary embodiment of the present invention.

Figure 3 is a cross-sectional view of a coated article made using the process of Figure 2 according to an exemplary embodiment of the present invention.

Figure 4 is a cross-sectional view of an IG window unit that includes a coated article of Figure 3 according to an exemplary embodiment of the present invention.

Detailed Description of the Examples of the Invention

Reference is now made more particularly to the drawings

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companions where equal reference numbers indicate equal parts in the various views.

Certain exemplary embodiments of the present invention relate to methods of manufacturing coated articles that can use heat treatment (HT), where the coated article includes a coating (one or more layers) including diamond-type carbon (DLC). In certain cases, HT may involve heating a supporting glass substrate, with the DLC on it, to temperature (s) from 550 to 800 ° C, more preferably from 580 to 800 ° C (which is well above the burning temperature of the DLC). In particular, certain exemplary embodiments of the present invention relate to a technique for allowing the DLC to support such an HT without significantly burning during it. In certain embodiments, a protective layer of sacrifice is formed on the glass substrate on the DLC in order to reduce the likelihood of the DLC burning during the

HT. In this way, most (if not all) DLC remains on the glass substrate, and does not burn, during HT. Following the HT, the sacrificial protection layer may or may not be removed in modalities other than the present invention.

Figure 1 is a cross-sectional view of a coated article20 according to an exemplary embodiment of the present invention. Typically, the coated article of Figure 1 exists during a manufacturing stage before heat treatment, but there may also be post-HT in certain cases. The coated article shown in Figure 1 includes glass substrate 1, at least one barrier layer 6, layer 11 including DLC ​​and sacrificial protection layer 17. The glass substrate 1 is typically made of or includes soda-lime-silica glass, although other types of glass may be used in certain cases.

Barrier 16 is provided to prevent or reduce oxygen and / or sodium (Na) from migrating from glass 1 to DLC 11 during HT. In this regard, barrier layer 6 improves the general optical characteristics of the post-HT coated article. Barrier layer 6 is preferably of or includes silicon oxide, silicon nitride, silicon oxynitride, and / or the like, although

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other barrier materials can also be used. Unexpectedly, it has been found that the use of silicon oxide as a barrier layer 6 (compared to silicon nitride) often leads to improved optical results of the final product after heat treatment such as increased visible transmission. Any of the aforementioned barrier layer 6 materials can be doped (for example, 0.5 to 15%) with Al, stainless steel or any other metal (s) in certain embodiments of the present invention. Barrier layer (s) (6) is / are formed on the glass substrate 1 by deposition, or by any other suitable technique. The barrier layer 6 can be from about 10 to 1,000 µm thick in certain exemplary embodiments, more preferably from 50 to 500 µm thick, and more preferably from 50 to 200 µm of thickness.

Layer 11 including DLC ​​can be from about 5 to 1,000 angstroms (Â) thick in certain exemplary embodiments of the present invention, more preferably from 10-300 Å thick, and most preferably from from 45 to 65 Â in thickness. In certain exemplary embodiments of the present invention, the DLC layer 11 may have an average stiffness of at least about 10 GPa, more preferably at least about 20 GPa, and most preferably from about 20-90 GPa Such stiffness makes the layer (s) 11 resistant to scratches, certain solvents and / or the like. Layer 11 may, in certain exemplary embodiments, be of or include a special type of DLC known as highly tetrahedral amorphous carbon (t-aC) and may be hydrogenated (taC: H) in certain embodiments. In certain hydrogenated embodiments, the type of DLC t-aC may include from 1 to 30% hydrogen, more preferably from 5-20% H and more preferably from 10-20% This type of t-aC DLC includes more carbon-carbon sp connections³ (C - - C) than carbon - carbon sp bonds² (C - - C). In certain exemplary embodiments, at least about 50% of the carbonocarbon bonds in the DLC layer 11 can be carbon-carbon bonds sp³(C - - C), more preferably at least about 60% of car connections ·· · · · ··· · ··· · · ··· ··· • ··· ·· ··· · · • ···· ···· ·· · · bono-carbon in layer 11 can be carbon bonds - carbon sp³ (C - C) and more preferably at least about 70% of the carbonocarbon bonds in layer 11 can be carbon - carbon sp bonds³ (C - - C). In certain exemplary embodiments of the present invention, the DLC can have an average density of at least about 2.4 gm / cm³, more preferably at least about 2.7 gm / cm³.

Exemplary linear ion beam sources that can be used to deposit layer 11 including DLC ​​on substrate 1 include any of those in US Patent No. 6,261,693, 6,002,208, 6,335,086 or 6,303,225 (all incorporated herein) as a reference). When using an ion beam source to deposit layer (s) 11, hydrocarbon feed gas (s) (for example, C₂H2), HMDSO, or any other suitable gas, can be used in the ion beam source in order to cause the source to emit an ion beam towards the substrate 1 to form the layers (11). It is noted that the stiffness and / or density of the layer (s) 11 can be adjusted by varying the ion energy of the deposition apparatus.

The DLC layer 11 allows the coated article to be more resistant to scratching than if the DLC layer 11 was not provided. It is noted that while the layer 11 is on the glass substrate 1 in certain embodiments of the invention, additional layer (s) 6 may or may not be under layer 11 between substrate 1 and layer 11 in certain exemplary embodiments of present invention. In this way, the sentence on the substrate as used here is not limited to being in direct contact with the substrate since other layer (s) can be provided between them.

For example and without limitation, layer 11 of or including DLC ​​can be any of the layers including DLC ​​of any US Patent No. 6,592,993; 6,592,992; 6,531,182; 6,461,731; 6,447,891; 6,303,226; 6,303,225; 6,261,693; 6,338,901; 6,312,808; 6,280,834; 6,284,377;

6,335,086; 5,858,477; 5,635,245; 5,888,593; 5,135,808; 5,900,342 or 5,470,661 (all of these patents being incorporated herein by way of reference ·· · · · ··· · ··· · · ··· ··· • ··· ·· ··· · · • ···· ···· ·· · · reference), or alternatively it can be any other suitable type of layer including DLC. Layer 11 including DLC ​​can be hydrophobic (high contact angle), hydrophilic (low contact angle), or neither, in different embodiments of the present invention.

The sacrificial protection layer 17 is provided in order to protect the DLC layer 11 during HT. If layer 17 was not provided, the DLC would oxidize significantly during HT and burn, thereby rendering the final product without defense against scratching. However, the presence of the sacrificial protection layer 17 prevents or reduces the amount of oxygen that can reach DLC 11 during HT from the surrounding atmosphere, thereby preventing the DLC from oxidizing significantly during HT. As a result, after HT, the layer 11 including DLC ​​remains on the glass substrate 1 in order to provide scratch and / or similar resistance.

It has been surprisingly found that the use of zirconium nitride (eg, ZrN) in a sacrificial protection barrier layer 17 is especially beneficial with regard to reducing and / or preventing oxygen diffusion in the DLC during HT. The sacrificial barrier layer 17 of or including zirconium nitride can be from about 300 to 600 Ã… in thickness in certain exemplary embodiments of the present invention, more preferably from 450 to 480 Ã… in thickness. Zirconium nitride is a very dense material and provides an excellent barrier against diffusion of oxygen in DLC during HT.

In certain exemplary embodiments of the present invention, zirconium nitride layer 17 may have a density of at least 6 gm / cm³, more preferably at least 7 gm / cm³. Furthermore, in certain exemplary embodiments, the zirconium nitride layer 17 may have an average stiffness of at least 650 kgf / mm, more preferably at least 700 kgf / mm and / or may have a population of overlapping hair binding minus 0.25 (more preferably at least about 0.30) for resistance purposes. In certain exemplary cases, many of the Zr-N bonds in layer 17 are of the covalent type, which are stronger than ionic bonds, for resistance purposes. It is also noted that in ·· · · · ··· · ··· · · ··· ··· • ··· ·· ··· · · • ···· ···· ·· · · certain Exemplary embodiments of the present invention, the layer 17 ZrN may have a melting point of at least 2,500 ° C, and may be from about 2,980 ° C in certain exemplary cases.

The zirconium nitride of layer 17 may or may not be doped with 5 other material (s) in different embodiments of the present invention. In certain exemplary embodiments of the present invention, layer 17 zirconium nitride is not doped with any other material. However, in other exemplary embodiments of the present invention, layer 17 zirconium nitride can be doped with Cu and / or Ni (for example, from about 0-15%, more preferably from about 1-10%) in order to provide more stability and / or resistance. The presence of dopant such as Cu and / or Ni in the ZrN can help the ZrN to be more stable during HT and can, for example, prevent or reduce phase changes (eg a change to ZrO) from ZrN during HT . In addition, in certain cases e15 xemplares, doping Ni in the ZrN layer 7 can serve as an oxygen absorber in the ZrN layer, thereby allowing layer 7 to function better as an oxygen barrier preventing or reducing the diffusion of oxygen in the DLC 11 over HT.

In certain exemplary embodiments of the present invention, the zirconium nitride of layer 17 can be represented by Zr_xN_y, where the ratio of x: y is from 0.8 to 1.2, and is preferably about 1.0 in certain exemplary embodiments.

In other exemplary embodiments of the present invention, the Zr in layer 17 can be replaced by Cr (or NiCr). Thus, in such embodiments, layer 17 may comprise CrN, where the CrN layer may or may not be doped with Ni or similar in the manner and quantity (s) explained above.

An exemplary process for making a window unit or the like will now be described, with reference to Figures 2-3. Initially, as shown in Figure 2 (a), the glass substrate 1 is provided, and at least one barrier layer 6 (for example, silicon oxide, silicon nitride, silicon oxynitride or similar) is deposited on a surface ·· ♦ · · ··· · ··· · · ··· ··· • · · ··· ··· · · • ···· ···· ·· · · his. Optionally, a multilayer solar control coating (not shown) can be deposited (for example, by deposition) on the surface of the glass substrate 1 opposite the barrier layer 6. As shown in Figure 2 (b), at least a layer 11 of or including DLC ​​is deposited (for example, by ion beam deposition) on the glass substrate 1 on at least the barrier layer 6. Then, as shown in Figure 2 (c), a protective layer 17 is deposited on substrate 1 on layer 11 including DLC. The protective layer 17 can be deposited through deposition, CVD, ion beam deposition or any other suitable technique. In an exemplary embodiment of the present invention, the protective layer 17 can be of or includes zirconium nitride as explained above.

Although layer 17 may comprise zirconium nitride in certain embodiments, the present invention is not so limited. Alternatively, instead of zirconium nitry, layer 17 may be of or include one or more of: chromium nitride, nickel-chromium nitride, amorphous silicon, silicon nitry, silicon oxide, silicon oxinitride, BC_X (boron carbide where x is from 0.75 to 1.5), TiC_x (titanium carbide, where x is from 0.47 to 0.99 - this can be oxidation resistance), HfC_x (hafnium carbide, where x is from 0.47 to 0.99), TiHf_yC (titanium hafnium carbide, where in certain non-limiting examples, x can be from about 0.6 and y can be about 0.4), TaC_x (titanium carbide, where x is from 0.47 to 0.99), ZrC_x (zirconium carbide, where x is from 0.47 to 0.99), Cr, NiCr, NiCrO_x, Ti, a removable paste of magnesium oxide and / or TiO_x. Certain of these materials are discussed in US Patent Application No. 10 / 091,589 filed on March 7, 2002, the description of which is incorporated herein by reference.

Optionally, a thin protective layer comprising DLC ​​or similar (not shown) can be provided on the sacrificial layer 17 before HT, in order to prevent layer 17 from peeling too early (i.e., to prevent the sacrificial layer 17 peel before HT or during early HT stages). An example of such a ····· ·· 9 9 · • · · β · ··· 9 9 9 · • · 9 9 ··· · 999 9 · 999 999 • 99 99 999 9 9

9999 9999 99 9 9 protection (not shown) is a thin layer of DLC about 10-30 μ thick, or any other suitable material that can burn during HT or can be easily removed after HT. Such a thin DLC layer (not shown) on the sacrifice layer 17 would burn quickly during HT.

As shown in Figure 2 (c), the glass substrate 1 with at least layers 6, 11 and 17 on it is then heat treated (HT) for purposes of thermal quenching, heat bending, heat reinforcement and / or similar. At least part of this HT can be conducted, for example, in an atmosphere including oxygen as known in the art at temperature (s) from 550 to 800 ° C, more preferably from 580 to 800 ° C (ie ie, temperature (s) above the burning temperature of the DLC). HT can last at least one minute, more preferably 110 minutes, in certain exemplary non-limiting embodiments of the present invention. During HT, the presence of protective layer 17 protects layer 11 containing HT DLC and prevents layer 11 from burning due to significant oxidation. Although in some cases a little of layer 11 can burn during HT, most, if not all, layer 11 including DLC ​​remains on substrate 1 even after HT due to the presence of the protective layer 17.

A significant advantage associated with the use of zirconium nitride in layer 17 is its ease of removal after HT. Protective layers such as silicon nitride are sometimes undesirable since they require a complex notch in order to remove them after HT. On the other hand, it has been found that when layer 17 is made of zirconium nitride, layer 17 tends to begin to peel on its own and / or be easily removed after HT. The zirconium nitride layer 17 is believed to be very easy to remove from DLC 11 after HT due to stress associated with layer 17 and the thermal mismatch between layers 11 and 17. In particular, the intrinsic compressive stress of the layer zirconium nitride 17, combined with the thermally induced stress in it in the same direction, causes the delamination of layer 17 either to happen automatically12 or to happen easily after HT.

The removal of the zirconium nitride layer 17 from the DLC after HT can be assisted by rubbing the article coated with Windex®, water, alcohol, a solution including ammonium hydroxide and / or similar. Scrubbing with such liquids can be especially beneficial in removing layer 17 after HT when the coated article is still hot from it (for example, when layer 17 is from about 80-200 ° C, more preferably from about 100-180 ° C).

After layer 17 has been removed, the remaining coated article is shown in Figure 3 and includes an outer layer comprising scratch resistant DLC. The aforementioned processes are advantageous in that they provide a technique for allowing a coated article including a layer including protective DLC to be heat treated without the DLC layer burning during such HT. In other words, it is possible to provide a layer including protection DLC 11 in a product in a commercially acceptable manner.

According to certain exemplary embodiments of the present invention, articles coated here do not lose more than about 15% of their visible transmission due to HT, more preferably not more than about 10%. In addition, monolithic coated articles here preferably have a visible transmission after HT of at least about 70%, more preferably at least about 75%. As an example, visible transmission of a monolithic coated article can drop from about 85% to about 78% due to HT.

The coated article of Figure 3 can be used in various applications, including, but not limited to, IG window units, laminated vehicle windscreens, other types of vehicle windows, furniture applications and / or the like. As an example, the coated article in Figure 3 can be used in an IG (insulating glass) window unit as shown in Figure 4.

The IG window unit of Figure 4 includes first glass substrate 1 and a second glass substrate 3 that are sealed together and / or • · · ····· · ···· ο * · «·« · • · · · And · »» · * * ··· * ···· · · · · · spaced one by the other through one or more spacers / fences 5. The gap or gap 7 defined between the opposing substrates 1 and 3 may or may not be filled with gas (e.g., Ar) and may or may not be evacuated to a pressure less than atmospheric in different embodiments of the present invention. The glass substrate (s) 1 and / or 3 can (s) be soda-lime-silica glass (for example, made using the known flotation process), or any other suitable type of glass (for example, glass borosilicate) in different embodiments of the present invention. Each substrate 1 can be from about 1 to 10 mm thick, preferably from 2 to 5 mm thick, and more preferably from about 2.5 to 3.6 mm thickness in certain exemplary embodiments of the present invention.

Still referring to Figure 4, optionally, substrate 1 and / or 3 can have a solar control coating (for example, coating with little multilayer E) (not shown) provided on an interior surface of it facing the other substrate. For example and without limitation, the solar control coating may include any of the coatings in any US Patent No.^s 5.688.585, 5.557.462, 4.898.790, 5.514.476, 3.682.528, 5.376.455, 5.337.045, 5.514.476, 5.770.321, 5.902.505,

5,942,338, 6,059,909, 6,060,178, 6,132,881 or 6,159,607 or US Serial No. 09,794,224 (see WO 02/04375) all incorporated herein by reference in their entirety. Many of these solar control coatings include at least one (and sometimes multiple) IR reflective layers (for example, including either Ag and / or NiCr) interspersed between a pair of dielectric layers; where the dielectric layers may or may not contact the Ag or NiCr. However, the present invention is not so limited, and any other type of solar control coating can be used on the contrary in different cases. In certain exemplary embodiments of the present invention, the GI window unit of Figure 4 has a visible transmission of at least 50%, more preferably at least 60% and in some cases at least 70%.

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For exemplary purposes and without limitation, the exemplary coating article that follows has been made and tested in accordance with an exemplary embodiment of the present invention. A silicon nitride barrier layer 6 of about 100 Å thickness, a DLC (type ta-C: H) 11 of about 70 Å thick and a sacrifice protection ZrN barrier layer 17 of about 460 µm thick were deposited on a soda-lime-silica glass substrate 1 as shown in Figure 1. Prior to heat treatment, the coated article had a visible transmission of over 80%. The coated article was then heat treated at a temperature of about 625 ° C. As a result of this heat treatment, the sacrifice ZrN layer 17 began to detaminate from DLC 11 alone due to stress induced by a lack of combination both intrinsic and thermal. Layer 17 was then dried using a paper towel and Windex®. The visible transmission of the monolithic coated article after heat treatment and after layer 17 had been wiped was as high as 78%. The scratch load for the sample was over 22.68 kg (50 Ibs), although it may be less than that in certain modalities.

Finally, it is noted that an XPS graph (not shown) indicated that as a result of HT, Si and N from a silicon nitride barrier layer 6 they can migrate to DLC layer 11 at least in an interface portion of it, as well as some oxygen. However, this is not particularly problematic since only small amounts of oxygen are involved. In addition, after HT, there are typically virtually no traces of Zr on the DLC surface after removal of the aforementioned ZrN.

Although the invention has been described in relation to what is considered here to be the most practical and preferred modalities, it should be understood that the invention should not be limited to the described modalities, but on the contrary, it is intended to cover various modifications and equivalent provisions included in the spirit and scope of the attached claims.

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