Definition

Class 216 is an integral part of Class 156. It incorporates all the definitions, rules, and hierarchy pertaining to subject matter of Class 156.

GENERAL STATEMENT OF CLASS 216 SUBJECT MATTER:

This is the Generic class for chemical etching processes for treating articles of commerce or intermediate articles not otherwise provided for in which one of the manufacturing steps includes a chemical etching step (use of an etchant) and wherein the material treated is not completely removed.

(1) Note. The chemical etching required for placement in this class is any intentional change of shape of an article or substrate by the removal of material involving a chemical reaction or physical solvation using a chemical agent (the etchant). This is the residual class for removing a surface by chemical reaction or solvent action regardless of the substrate acted on. Bright Polishing of a metal with acid solution is considered etching and appropriate for this class. The processes of the patents in this class often include the formation of a design, but the production of a design is not required to place the patents here. (2) Note. Reduction in size using a chemical etchant of an unmasked article, substrate or unmasked geometric figure, e.g., sphere, etc. is proper for this class. (3) Note. Etching of a masked article, to direct the etchant to only a portion of the article or substrate is proper for this class. (4) Note. This class is not intended for the total dissolving of an article or substrate. Furthermore, the remaining article or substrate must be the desired product and not the removed material. An example of a process not proper for Class 216 would be ore beneficiating where the dissolved material is what is desired and useful and not the remaining residue material. Additionally a process of dissolving out impurities or unwanted material to leave a desired article is proper for this class when said process is not provided for elsewhere. (5) Note. Chemical milling is considered within the scope of the term etching. (6) Note. Class 216 provides only for etching processes. Etching compositions are elsewhere. See Lines With Other Classes, below.

Lines with other classes and within this class

Class 216 is an integral part of Class 156. It incorporates all the definitions, rules, and hierarchy pertaining to subject matter of Class 156.

Etching compositions are in Class 252, subclasses 79.1-79.4 (see the class line below in regards to Class 252 and nominal etching processes) and etching apparatus is classifiable in Class 156, subclasses 345.1-345.55. Compounds dis as useful in etching are classified in the respec compound classes and articles which are produced as the result of an etching process are classified in the appropriate article class or stock material class.

A. SPECIAL CLASS LINES

1. CLASS 29, METAL WORKING

Class 216 has several important relationships with this Class 29. Both classes take designated single-step processes, and both are locations for multistep processes for manufacturing designated products or using certain combinations of steps.

Single-step processes to produce a Class 29 special product, include shaping particulate metal by pressure alone. In addition Class 29 provides, for example, for processes of burnishing, filing, or the mechanical joining of parts to manufacture the special article. Where only an etching step is claimed, the process is assigned to Class 216, even though a product designated for Class 29 is manufactured.

Multistep processes for Class 29 are of two types: (a) Those for making specified articles, enumerated in that part of Class 29 schedule which precedes subclass 400.1.; (b) Multistep manufacturing processes not provided for elsewhere.

Insofar as processes of type (a) are concerned, these are assigned to Class 29, even when an etching step is claimed as part of the multistep process, except for processes classifiable in subclasses 825+, which follows the category (b) rule given in the next paragraph.

Processes of type (b) are provided for in Class 216 when they claim: (1) Etching combined with the shaping of a nonmetal; (2) Etching either nominal or specific combined with broad or nominally claimed metal shaping steps; (3) Specific etching including steps for assembling parts that have been etched or are to be etched;

Processes of type (b) are classified in Class 29 when they claim: (1) Nominal etching combined with specific metal shaping steps; (2) Nominal etching combined with mechanical joining, either broad or specific.

2. CLASS 438 SEMICONDUCTOR DEVICE MANUFACTURING: PROCESS.

Classification is proper for Class 438:

(1) When the specification contains only disclosure of semiconductive material, precursor, substrate, or device and the claims are generic in nature the classification is proper for Class 438.

(2). When the specification contains disclosure to species of semiconductive material, precursor, substrate, or device and nonsemiconductive species and the claims are directed to the semiconductive material species only classification is proper for Class 438.

(3) When the specification contains disclosure to species of semiconductive material, precursor, substrate, or device only and the claims are directed to semiconductive material species only classification is proper for Class 438.

Classification is proper for Class 216:

(1) When the specification contains disclosure to species of semiconductive material, precursor, substrate, or device and nonsemiconductive species and the claims are generic in nature the classification is proper for Class 216 Etching.

(2) When the specification contains disclosure to species of semiconductive material, precursor, substrate, or device and nonsemiconductive species and the claims contain semiconductive species and nonsemiconductive species classification is proper for Class 216 Etching.

(3) When the specification contains disclosure to semiconductive material used in a nonelectrical function and the claims contain semiconductive material used in nonelectrical function classification is proper for Class 216 Etching.

B. GENERAL LINE WITH OTHER CLASSES

1. CLASS 134 CLEANING AND LIQUID CONTACT WITH SOLIDS

Class 134 is noted for cleaning processes wherein a surface is treated to remove or separate unwanted adherent material, e.g., dirt, scale, coatings, etc. Class 134, subclasses 1.1 through 1.3 provide for processes of cleaning using a plasma and for cleaning of semiconductive material. Subclasses 2 and 3 are noted for chemical bleaching, oxidation, or reduction of a metallic siliceous or calcareous base.

2. CLASS 204 CHEMISTRY: ELECTRICAL AND WAVE ENERGY and CLASS 205 ELECTROLYSIS: PROCESSES, COMPOSITIONS USED THEREIN AND METHODS OF PREPARING THE COMPOSITIONS

Chemical etching performed on a composition, product, or article made by a Class 204 process (e.g., an entire article previously etched by electrolysis, a product portion modified by electrolytic material treatment, etc.) is considered to provide a significant modification of the composition, product, or article made by the Class 204 process, therefore placing the combination of a Class 204 process followed by Class 216 chemical etching in Class 216. However, the combination of a Class 205 electrolytic coating step followed by Class 216 chemical etching performed (1) to allow at least a portion of the electrolytic coating to remain and (2) to only significantly modify the electrolytic coating, per se, is considered to be an electrolytic coating process followed by a mere perfecting step for the electrolytic coating, therefore placing the combination in Class 205. The significant modification of only the electrolytic coating allows for mere incidental alterations to other portions of a coated article such as the substrate provided that such changes are clearly unintentional (e.g., chemical etching through an electrolytic coating which may also progress into the substrate in some areas to allow complete penetration through all desired other areas of the electrolytic coating, etc.). Class 216 also provides for the original classification when the claims are alternative (claims to a Class 216 process and claims to a Class 205 electrolytic etching, or when a generic claim is present and no species is specifically claimed). When, however, a generic claim is present (disclosure includes both Class 216 and Class 204 or Class 205 subject matter) and a Class 204 or Class 205 species is specifically claimed, and there is no specific claim to a Class 216 etching process, the original classification is in Class 204 or Class 205 and a mandatory cross-reference is placed into Class 216 based on the generic claim.

Other combinations of Class 204 step(s) with Class 216 step(s) will follow the general class line for the combination of Class 204 step(s) with those from other classes as stated at the beginning of Class 204. In particular, see Class 205, subclasses 123+, for electrolytic coating of or with semiconductor material, subclasses 125+ for electrolytic coating to produce a circuit board or a printed circuit, subclasses 206+ for contacting a substrate with a solid member or material (e.g., polishing, rolling, etc.) combined with a subsequent step of electrolytic coating, subclasses 210+ for treating a substrate with a liquid other than tap water (e.g., chemical etching, etc.) combined with a subsequent step of electrolytic coating, subclasses 640+ for electrolytic erosion of a workpiece to change the shape or surface configuration thereof, and subclasses 687+ for electrolytic material treatment, in general (e.g., electrolytic stripping of an entire coated layer from a substrate, etc.).

3. CLASS 219 ELECTRIC HEATING

See Class 219, subclasses 121.36+ for removing or altering material by the use of a high temperature thermal plasma. Class 216 provides for the use of a cold plasma which is a chemical etching process involving reactive ions and a substrate whereas the high temperature thermal plasma proper for Class 219 alters the substrate solely by thermal means. Class 219 subclasses 68+ provide for processes of cutting or disintegrating metal by metal heating, subclasses 121.19+ for processes of using an electron beam or etching or trimming metal, subclasses 121.36+ for processes of using a high temperature thermal plasma to etch metal, and subclasses 121.6+ for processes of using a laser to etch metal.

4. CLASS 264 PLASTIC AND NONMETALLIC ARTICLE SHAPING OR TREATING: PROCESSES

Combinations of shaping a plastic material and etching the shaped product, or combinations of shaping, laminating, and etching are proper for Class 216. Laser ablation of a Class 264 material in the absence of an added reactive chemical is proper for Class 264, however, when a reactive chemical is used in the laser ablation process the process is classifiable in Class 216. Subclasses 22+ for the shaping of an article by removing a portion by electrical or wave energy, e.g., laser ablation wherein no chemical etchant is employed, etc., subclass 49 for forming pores in situ by treating an occluded solid, subclasses 82+ for reactive gas or vapor treatment of an article, subclasses 211.12+ for processing or treating after extruding, subclasses 219+ for processes of preparing a mold which includes an etching step in the mold manufacture followed by a shaping operation, and subclass 341 for the solvent polishing of a shaped or solid article.

5. CLASS 427 COATING PROCESSES

Subclasses 307+ for processes limited to etching for making a base more compatible with or adherent to the coating wherein the base is the substrate (work) onto which a coating is to applied.

6. CLASS 430 RADIATION IMAGERY CHEMISTRY: PROCESS, COMPOSITION, OR PRODUCT THEREOF

For processes of radiation imagery including claimed exposing and finishing by a post imaging process, e.g., developing, etching, etc. or finishing an image, e.g., developing, etching, etc. where the claim is silent as to an exposure step.

Subclass 5 for producing a radiation mask, subclasses 313+ for a post imaging process of treating a resist to remove a portion of the same.