Definition

SUBJECT MATTER AND ORGANIZATION OF THIS CLASS

This class provides for a hydrocarbon compound in a pure or relatively pure state and for certain compositions containing hydrocarbons. Methods for making such compounds and compositions by synthesis, blending, etc., and certain methods for treating are also included herein. The scope of this class can be readily determined from a review of the "main line" subclasses of its schedule. These are arranged, in general, following the principles usually applied in the U.S. Patent and Trademark Office for hierarchically ordering statutory subject matter, that is, more complex subject matter or that which exists later in time is generally placed ahead of simpler or earlier subject matter. As applied to chemistry and chemical engineering this ordering is generally as follows:

A. Materials defined by structure.

B. Compositions or mixtures

C. Compounds or elements

D. Manufacturing processes, e.g., synthesis, etc.

E. Nonmanufacturing processes, e.g., purification, etc.

F. Manufacturing apparatus

G. Nonmanufacturing apparatus

This class is confined to categories B, C, D, and E of the above list.

At the heart of this class is the pure compound which consists of carbon and hydrogen and no other element and which has a definite empirical formula and an unambiguous structural formula.

The major portion of patents in this class is drawn to processes for synthesizing such compound from other materials which are not this exact compound, with the intent of recovering the hydrocarbon compound.

Also included in this class, with some exceptions, is a mixture of hydrocarbon compounds, usually closely related in empirical and structural formulae, which mixture results from a single synthesis step, or a series of steps, which mixture is of utility as a mixture, e.g., a "detergent alkylate", a "polymer gasoline", etc. The exceptions are discussed below.

This class also includes, again with some exceptions, a composition which is a deliberate mixture of various hydrocarbons only, such as a fuel or lubricant composition, or a mixture of a hydrocarbon with a nonhydrocarbon material, which nonhydrocarbon material is designed to improve the general utility of the hydrocarbon. Thus, the nonhydrocarbon additive may be a solvent, a preservative, etc.

This class also provides, again with certain exceptions, for methods of manufacturing compounds and compositions classifiable herein and for certain methods of purifying the same or otherwise treating the same.

Lines with other classes and within this class

This class is the residual class of all Patent Office classes concerned with categories B, C, D, and E listed above. See Class 588, Hazardous or Toxic Waste Destruction or Containment, subclasses 312-321 for the chemical destruction of hydrocarbon hazardous or toxic waste.

When a patent has a claim to subject matter for one of the categories B to E above and another claim to subject matter for another of these categories, the patent is assigned as an original to the class which provides for the "lowest" lettered category and is cross-referenced to such other classes as required by the claims and disclosure.

When a patent has a claim to subject matter in categories B or C of the above list, which subject matter is provided for in this class, and other claim to subject matter in this same category which is provided for in another class, the patent is placed as an original in the other class and cross-referenced to this class. For example, when one claim is to a solid resinous hydrocarbon polymer and another is to a liquid hydrocarbon polymer, the patent is classified as an original in the class which provides for the solid resinous polymer.

The rules for determining Class placement of the Original Reference (OR) for claimed chemical compositions are set forth in the Class Definition of Class 252 in the section LINES WITH OTHER CLASSES AND WITHIN THIS CLASS, subsection Composition Class Superiority, which includes a hierarchical Order of Superiority for Composition Classes.

For a compilation of Patent Office classes dealing with categories B and C above, see the definition of subclass 1 below. For a compilation of Patent Office classes dealing with category E above, see the definition of subclass 800 below.

As for category D, a process for manufacturing a composition or a chemical compound generally is provided for in the class which would provide for the composition or compound, per se, were it to be claimed. An exception to this rule is where another class provides for a particular synthesis procedure. The main classes of this type are the following, in order of priority:

Class 117, Single-Crystal, Oriented-Crystal, and Epitaxy Growth Processes; Non-Coating Apparatus Therefor, for processes for growing therein-defined single-crystal of all types of materials, including hydrocarbon.

Class 201, Distillation: Processes, Thermolytic, provides for the synthesis of chemical compounds or elements, including hydrocarbons, by elevated-temperature processes which leave a solid carbonaceous char, e.g., coke.

Class 204, Chemistry: Electrical and Wave Energy, for synthesis of chemical compounds or elements, including hydrocarbons, by electrical or wave energy, as provided for under the Class 204 definition.

Class 205, Electrolysis: Processes, Compositions Used Therein, and Methods of Preparing the Compositions, for electrolytic processes, including synthesis of chemical compounds or elements.

Class 435, Chemistry: Molecular Biology and Microbiology, provides for the synthesis of chemical compounds or elements, including hydrocarbons, by enzymatic action.

Class 518, Chemistry: Fischer-Tropsch Processes; or Purification, or Recovery of Products Thereof, provides for the synthesis of chemical compounds, including hydrocarbons, by the hydrogenation of carbon oxides.

If a synthesis process leads to two products, a hydrocarbon and a nonhydrocarbon, both of which are intended to be recovered from the process, the patent is classified as an original in the class providing for the nonhydrocarbon synthesis and cross-referenced to Class 585 when the hydrocarbon synthesis is proper for this class. For example, a process which treats an alkyl sulfate to recover both an olefin and sulfuric acid is placed in the class providing for sulfuric acid recovery.

Where a patent contains a claim to a multistep synthesis process for producing a nonhydrocarbon intermediate which is converted to a hydrocarbon and has another claim for synthesis only of the nonhydrocarbon intermediate, the patent is classified as an original in the class providing for synthesis of the intermediate, despite the fact that the claim for Class 585 is more "comprehensive".

When a patent has claims only to a multistep process which produces a hydrocarbon compound or mixture which would be classified in this class, and the final synthesis step is provided for in Classes 195, 201, or 204, the patent is classified in that class; where the step provided for in those classes is earlier than the final synthesis step, the patent is classified in Class 585.

Where a Class 201 synthesis step is not positively recited, that is, synthesis is performed upon mere hydrocarbon products of such step, classification is proper in Class 208 when a hydrocarbon mixture is obtained and in Class 585 when a relatively pure hydrocarbon compound is obtained.

Where a patent has only category E claims, the above rules do not necessarily apply. The complex classification lines which prevail among the purification classes are spelled out below, in the discussion of the hierarchical relationship among subclasses 800+ of this class and other areas.

LINE BETWEEN SUBCLASSES 800+ AND OTHER AREAS

Subclasses 800+ are residual and receive only those original patents not acceptable elsewhere. These "elsewheres" are dealt with in the Notes below, and are summarized as follows

(A) Separation or purification by electrical and or wave energy phenomena. - Class 204, Chemistry:Electrical Wave Energy. See (1) Note below.

(B) To produce mineral oil mixture - Class 208, Mineral Oils: Processes and Products. See (2) Note below.

(C) Involving the formation of an adduct of urea or thioreaor thiorea - Class 260, Chemistry of Carbon Compounds, subclass 96.5. See (3) Note below.

(D) Involving the formation of a hydrocarbon hydrate - Class 585, Chemistry of Hydrocarbon Compounds, subclass 15. See (4) Note below.

(E) Involving hydrogenation of an unsaturated bond of a hydrocarbon - Class 585, Chemistry of Hydrocarbon Compounds, subclasses 250+. See (5) Note below.

(F) Of gaseous feed - Class 95, Gas Separation: Processes. See (6) Note below.

. (G) Involving a chemical reaction - Class 423, Chemistry of Inorganic Compounds. See (7) Note below.

. (H) Involving liquefaction or solidification. Class 62, Refrigeration. See (8) Note below.

(I) Of liquid feed - Class 210, Liquid Purification or Separation. See (9) and (10) Note below

. (J) By distillation - Class 203, Distillation: Processes, Separatory. See (11) Note below.

. (K) By removal of gas or vapor - Class 95, Gas Separation: Processes.. See (12) Note below.

. . (L) To leave solids concentrate - Class 159, Concentrating Evaporators. See (13) Note below.

. (M) By chilling to solidify - Class 62, Refrigeration. See Note 14 below.

(N) By drying a solid - Class 34, Drying and Gas or Vapor Contact With Solids. See Note 15 below.

(1) Note. Where the purification process involves a chemical reaction due to electrical or wave energy (other than merely thermal) effects, or movement of ions or particles due to electrical "pressure" (electrophoresis or electroosmosis) classification in Class 204 is usually proper. (2) Note. Where the desired product is a mixture of hydrocarbons which can be considered a mineral oil fraction, classification is proper in Class 208, subclasses 177+ and 308+. (3) Note. Where the process involves the formation of an adduct of urea or thiourea classification in Class 260, subclass 96.5 is proper. (4) Note. Where the process involves the formation of a hydrocarbon hydrate (complex of hydrocarbon with water) classification is proper in this class (585), subclass 15. (5) Note. Where the process involves conversion of impurity in a desired hydrocarbon to more of the desired hydrocarbon, classification is proper in a synthesis subclass of this class (585). See, in particular, subclasses 258+. (6) Note. Where the feedstock is specified as being in gaseous form and the recovery process involves a chemical reaction, classification in Class 423, subclasses 210+ is usually proper. (7) Note. Where the feedstock is specified as being in gaseous form and the recovery process involves a chemical reaction, classification in Class 423, subclasses 210+ is usually proper. (8) Note. Where the feedstock is a normally gaseous material (e.g., a C₁-C₄ hydrocarbon) and separation is accomplished by removing heat, thereby liquefying or solidifying a component of the feed mixture, classification is proper in Class 62, subclasses 606+ and 617+. (9) Note. Where the feedstock is specified as being in gaseous form and the recovery process does not meet the limitations of (11) Note or (12) Note above, classification in Class 95 is usually proper. (10) Note. Where the feedstock is a liquid mixture and separation is accomplished by vaporizing and condensing a component of the mixture, classification in Class 203 is usually proper. Such classification is also proper when a chemical reaction which facilitates distillation takes place before the distillation and/or a disparate separation procedure, not involving a chemical reaction, follows the distillation. Classification in Class 203 also is usually proper when an additional agent is added to dissolve a desired or undesired component, adjust the boiling point of the mixture, etc., (extractive distillation). See also the note in the class definition of this class (585) to Class 201, Distillation: Processes, Thermolytic. (11) Note. Where the feedstock is a liquid mixture and a component is removed as a gas without subsequent condensation, classification is usually proper in Class 95, subclasses 241+. (12) Note. Where the feedstock is a liquid solution or a suspension of solids in a liquid and the separatory process is the evaporation of a component, without subsequent condensation of vapor, to leave a fluent concentration of solids or a dry solid, classification in Class 159 is usually proper. (13) Note. Where the feedstock is a liquid mixture and separation is accomplished by chilling to solidify (crystallize) a component of the mixture, classification is as follows: (a) Where no non-hydrocarbon organic compounds are disclosed and a hydrocarbon compound is separated or purified or a hydrocarbon hydrate is formed, placement is proper in Class 585, especially subclasses 812+. (b) Placement is to Class 260, including the related classes, for processes of treating or modifying claimed or disclosed non-hydrocarbon organic compounds: by crystallization wherein the crystallization is not brought about by refrigeration; or wherein crystallization, by any means including refrigeration, is combined with synthesis or modification of carbon compounds by chemical means; or wherein separation of carbon compounds is by physical means other than refrigeration. Otherwise placement is proper in Class 62 when refrigeration is claimed. (c) Placement is to Class 62 where no specific (i.e., classifiable) compound is disclosed. (d) Placement is proper for Class 117 for processes forming single-crystals of all types of materials, including inorganic or organic, and by all techniques. See the Class 117 definitions for guidance in placement of single-crystal art. (14) Note. Where the separation of a liquid feed is by flocculation, filtration, gravity settling, or magnetic attraction of solids already present in the feed, classification in Class 210 is usually proper. (15) Note. Where separation of liquid feed is by phenomenon other than those recited in notes 14-18, classification in Class 210 is usually proper when (a) water is claimed as the product or a species of product to be recovered or (b) no species of product is claimed and water is disclosed as a recoverable species. (16) Note. Where the feed is a solid or slurry of solid and liquid is evaporated from the feed, classification in Class 34 is usually proper. If the starting material is in the form of a liquid suspension or solution, even if the process is continued to the point of complete dryness, Class 159 will take the process. The removal of water of crystallization is considered a chemical synthesis for this class (585). LINE WITH CLASS 208 The subject matter of Class 208, Mineral Oils: Processes and Products, is closely related to the subject matter of this class and constitutes a subset restricted as to product, feedstocks to the processes, and materials recovered from the process. Class 208 provides for the treatment of generally liquid (oil) feedstocks which have come out of the ground (mineral) or liquid feedstocks of nonmineral origin which cannot be readily distinguished from mineral feedstocks. The treatment given such feedstocks must result in a mixture of compounds if it is to be classified in Class 208 as a product or a process. Reaction of a Class 208 material with small amounts of nonmineral oil hydrocarbons will not take a process out of Class 208, but a claim to a product mixture of mineral oil and nonmineral oil material usually will serve to assign such product to Class 585. Conversion of a Class 208 feedstock to a nonhydrocarbon intermediate and subsequent conversion back to a hydrocarbon mixture is provided for in Class 585. Conversion of a mineral oil feedstock to normally gaseous hydrocarbons (C₄ or less) and reconversion of such gases back to a liquid hydrocarbon compound or mixture is provided for in Class 585. Besides those hydrocarbon mixtures which have been recovered from the earth as a liquid, i.e., petroleum, other feedstocks which qualify a process for placement in Class 208 are those mainly hydrocarbon feedstocks derived from solid natural products, e.g., coal, wood, asphalt, etc., and "Fischer-Tropsch" crudes, that is, those derived from the Fischer-Tropsch synthesis which is the subject matter of Class 518, subclass 700. The scope of the purification and separation treatments included in Class 208 differs from those included in Class 583, mainly in that Class 208 takes its own distillation processes.