Raw cannabis contains tetrahydrocannabinol carboxylic acid (THC-COOH); this substance is also referred to as THC acid, Δ9-THC acid, THCA-A, or THCA.
The article that appears in the Journal of Chromatography “Innovative development and validation of an HPLC/DAD method for the qualitative determination of major cannabinoids in cannabis plant material” reference [1], see section 1.1; this article reports that THC-B is another form of THC acid that appears only in trace amounts in raw cannabis. This article also reports other substances in raw cannabis, including cannabidiolic acid (CBDA) and cannabigerolic acid (CBGA); a substance cannabinol (CBN) is also reported present in aged cannabis. 
THC acid may be converted into the psychoactive substance Tetrahydrocannabinol (THC), also known as (Δ9-THC) through processes that decarboxylate the THC acid. Decarboxylation is a chemical reaction that converts an acid to a phenol and releases carbon-dioxide (CO2); a carbon atom is removed from a carbon chain.
Reference [1] also discusses and shows the decarboxylation of THC acid into Δ9-THC, the decarboxylation of cannabidiolic acid (CBDA) into cannibidiol (CBD), and the decarboxylation of cannabigerolic acid (CBGA) into cannabigerol (CBG). Decarboxylation occurs when cannabis is exposed to heat, light, cofactors or solvents.
Historical and anecdotal reports of the medicinal use of cannabis date back for millennia, in recent decades the psychoactive ingredient Δ9-THC has been extracted through a verity of processes; to date processes that decarboxylate of THCA-A into psychoactive Δ9-THC in controlled ways use toxic solvents; frequently a distillation process such as fractal distillation is then used to separate the toxic solvents from the active ingredient after decarboxylation.
THCA-A decarboxylated into Δ9-THC in controlled ways using toxic solvents:
Related U.S. Pat. Nos. 6,365,416 B1 [2], 6,730,519 [3]; and patent publication US 2002/0039795 A1 [4] by Elsohly et. al. isolates Δ9-THC from cannabis base material using toxic non-polar organic solvents such as hexane, heptane, or iso-octane. U.S. Pat. No. 6,730,519 [3] was sponsored by a National Institute for Drug Abuse, Small Business Innovative Research grant; Related U.S. Pat. Nos. 6,365,416 [2] and 6,730,519 [3] in their Background of the Invention section provide excellent details regarding the medical use of Δ9-THC. the inventors conclude that extracting Δ9-THC from raw cannabis material is more cost effective than synthetically created FDA approved medicinal THC, and they reference prior art dating from 1942 through 1972 that relate to THC extraction or analysis of hashish and “red oil”; the processes referenced frequently use toxic elements such as carbon tetrachloride, benzene, N-dimethyl formamide/cyclohexane, or hexane.
U.S. Pat. Nos. 7,524,881 B2 [5], and 7,592,468 B2 [6] Goodwin et. Al. discloses processes that extract Δ9-THC from raw cannabis; this process converts THC acid into salt using non-polar solvents such as pentane, hexane, heptane, or octane; again toxic solvents are used.
GW pharmaceuticals of Great Britain has created a vaporized form of medicinal Δ9-THC called Savitex.
Savitex is administered with an inhaler, similar to an inhaler used to administer asthma medication. Information regarding the therapeutic use and mechanisms of action of Savitex can be found on GW pharmaceuticals website. Savitex is currently being studied for affectivity by patients with multiple sclerosis, cancer pain, and neuropathic pain.
GW pharmaceutical reports that the human body has receptors to frequently called CB1 and CB2 and that Δ9-THCbonds to CB1 receptors located in the human brain, where cannabinoids bond to CB2 receptors located in the human lymphatic system. The URLs below link to reports on GW Pharmaceuticals website, they describe that Savitex is being used medicinally and describe some of the mechanisms of action of medicinal cannabis; these reports have also been combined into reference [7]:
http://www.gwpharm.com/multiple-sclerosis.aspx
http://www.gwpharm.com/cancer-pain.aspx
http://www.gwpharm.com/neuropathic-pain.aspx
http://www.gwpharm.com/mechansims-action.aspx
The science related to how these various substances affects the human body is in its infancy, even so GW pharmaceuticals of Great Britain reports that the human body has receptors CB1 and CB2 to which Δ9-THC and CBD (cannabidiol) bond respectively. They also report that the human body has CB1 receptors predominately located in the human brain, and CB2 receptors located predominantly in the human lymphatic system.
Most reports indicate that psychoactive substance Δ9-THC is the primary active medicinal substance derived from cannabis; other substances contained within cannabis may however also have medicinal qualities. Some researchers suspect that cannabidiol (CBD) may mitigate pain; more scientific research is needed to understand how the various substances derived from cannabis affect the human body. GW Pharmaceuticals also state in their Mechanisms of Action “The combination of THC, CBD and essential oils in cannabis-based medicinal extracts may produce a therapeutic preparation whose benefits are greater than the sum of its parts”.
Reference [8] “Effects of canabidiol on schizophrenia-like symptoms in people who use cannabis”; from The British Journal of Psychiatry (2008) reports that Δ9-THC tends to “elevate levels of anxiety and psychotic symptoms in healthy individuals. In contrast, cannabidiol (CBD), another major constituent of some strains of cannabis, has been found to be anxiolytic and to have antipsychotic properties, and may be neuroprotective in humans”.                A key finding of this study [8]: “The TCH only group showed higher levels of positive schizophrenia-like symptoms compared with the no cannabinoid and the TCH+CBD groups . . . . This provides evidence of the divergent properties of cannabinoids and has important implications for research into the link between cannabis use and psychosis”.        
Reference [9] Therapeutic Potential of Non-Psychotropic Cannabidiol in Ischemic Stroke; Hayakawa, Mishima, & Fujiwara; Dept. of Neuopharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Published Jul. 8, 2010. Δ9-THC. This reference reviews various substances found within cannabis, it states in its introduction that “Cannabis contains over 60 different terpeno-phenol compounds that have been identified so far but the role and importance of many of these has yet to be fully understood”.                Reference [9] also states “cannabidiol (CBD), cannabigerol (CBG), cannabidvarin (CBDV) are known as non-psychoactive components of cannabis. These compounds have shown anti-inflammatory, immunosuppressive, analgesic, anxiolytic and anti-cancer effects”. This reference also discusses the neuroprotective abilities of CBD in stroke victims.        
The above mentioned references [7]. [8], and [9] demonstrate that Δ9-THC is not the only substance contained within medicinal cannabis with therapeutic benefits to people. All of these references recommend additional study or mention that the effect of the substances contained within cannabis on humans is not fully understood. Variations of ratios of substances contained within medicinal cannabis are reported to have different effects; as in reference [8], adjusting the ratio Δ9-THC to CBD is shown to be critical in limiting anxiety and psychotic symptoms associated with the intake of high concentrations of Δ9-THC as compared to CBD. New substances and therapeutic uses of substances derived from cannabis are likely to be discovered as research in this field continues.
Reference [10] “Isolation of Δ9-THCA-A from hemp and analytical aspects concerning the determination of Δ9-THC in cannabis products”; Dussy, et al. Institute of Legal Medicine, Basel Switzerland, available online Aug. 18, 2004. This reference quantifies the amount of THC acid (THCA-A) that is converted into Δ9-THC when cannabis is smoked under various conditions: Section 2 reviews cannabis reduced into a concentrated THC acid (THCA-A) solution using solvents. Samples of the concentrate are then decarboxylated at various temperatures in a Gas Chromatography (GC) oven; some samples are then analyzed using High Performance Liquid Chromatography (HPLC). FIG. 3 in this disclosure shows:                Partial decarboxylation of concentrated THCA-A in solution into Δ9-THC at 120 degrees C.        Significant decarboxylation of concentrated THCA-A in solution into Δ9-THC at 140 degrees C.        Nearly complete decarboxylation of concentrated THCA-A in solution into Δ9-THC at 160 degrees C. along with some degradation of Δ9-THC into cannabinol and dihydrocannabinol at 160 degrees C.        A significant percentage of Δ9-THC being degraded into cannabinol and dihydrocannabinol at 180 degrees C.        
The decarboxylation of concentrated THCA-A in solution into Δ9-THC, and the degradation of Δ9-THC into cannabinol and dihydrocannabinol are shown to vary with temperature. Temperature controls are therefore one mechanism for controlling ratios of certain substances in medicinal cannabis. 
Note: An embodiment of the invention described later in this document uses temperature and other mechanisms to control the decarboxylation of THCA-A in raw cannabis. 
Concentration ratios of THC acid (THCA-A) to cannabidiolic acid (CBDA) vary with the types cannabis selected; THCA-A decarboxylates into Δ9-THC, and CBDA decarboxylates into CBD.
Reference [11] is an example of cannabis related material available to the general public Wikipedia under “Cannabiniod” in August 2010. Many of the same substances discussed in previous references are also reviewed in reference [11].
Reference [12] Cannabis and Cannabis Extracts: Greater Than the sum of Their Parts?, by John M. McPartland and Ethan B. Russo; 2001 The Haworth Press, Inc. this reference reports the boiling temperature of cannabis related substances, the boiling temperatures reported include: Δ9-THC 157 degrees C., cannabidiol (CBD) 160-180 degrees C., cannabinol (CBN) 185 degrees C., and Δ8-THC 175-178 degrees C.
Reference [13] U.S. Pat. No. 7,674,922 “Process for Production of Delta-9-Tetrandrocannabinol”, Burdick et al. Granted Mar. 9, 2010. This reference produces Δ9-THC using “ortanoaluminum-based Lewis acid catalyst”, a metallic based catalyst.
Reference [14] a drawing from www.Cannabis-Science.com showing chemical structures in cannabis related materials. The drawing is entitled “Cannabinoids”; the drawing shows an important aspect of cannabinoid science, Cannabidiol (CBD) can be converted into Δ9-THC. The chemical structures are very similar, they have the same molecular weight and the same chemical formula. Reference [15] patent application publication US 2008/0221339 by Webster et al. published Sep. 11, 2008 discusses the conversion of Cannabidiol (CBD) to Δ9-THC and Δ8-THC are discussed in; various toxic solvents are used in these processes; one cannabis related substance is converted another through a chemical process.
Reference [16] Hemp Husbandry, an excerpt from Chapter 6 Cannabinoid Chemistry: Robert A. Nelson, Copyright 2000; another excellent review of the chemistry of cannabis 
Uncontrolled Crude Processes:
Other processes have been used to extract Δ9-THC from raw cannabis in uncontrolled ways, some of these processes use toxic materials and others do not; frequently such processes attempt to produce a final product in a single uncontrolled crude step.
Examples of such processes include the use of butane, a toxic solvent, to make the cannabis “red oil” commonly called hash oil. A method found on the internet reference [17] “How To Make Hash Oil from Marijuana” reviews the use of butane, here raw cannabis is saturated in butane, the butane reduces the raw cannabis into an oil that is separated from the plant material, the butane evaporates continuously during the process of reduction; a paper filter is used to separate the oil from plant material. The author also recommends a secondary process of mixing the oil with isopropyl alcohol, then evaporating the isopropyl alcohol overnight by letting it sit. The author of this reference believes that the isopropyl alcohol reduces the photosensitivity of THC contained within the oil. The process disclosed has no scientific controls, and shows disregard for laws relating to treating cannabis as a controlled substance or preparation of food products. The disclosure is provided as an example of uncontrolled methods that are available to the public.
In contrast, uncontrolled crude processes that use no toxic chemicals include simply baking cannabis into cookies or bread, or making a tea by steeping cannabis in hot water. Cannabis infused dairy butter can be made by melting dairy butter in a pot, adding raw cannabis and cooking the mixture for a period of time, up to 24 hours.
Hashish may be made without the use of toxic chemicals, “How to Made Wicked Hash” by Lisa Scammel and Bianca Sind [17] reviews various methods for separating THC acid infused trichomes from cannabis plant materials, forming it into blocks that are then covered in paper, and then heated in fry pan until the blocks melt; the processes reviewed are uncontrolled, and have no scientific controls, they include: “Flat Screening”, “Drum Machines”, “the blender method”, and “ice-water filtration” methods are reviewed. This reference is also provided as another example of uncontrolled crude methods that are available to the public. This disclosure also shows some disdain for laws relating to cannabis as a controlled substance.
Smoking, in the form of a cigarette or pipe, is the most frequently used uncontrolled process for decarboxylating cannabis. 
The processes discussed above that rely on temperature simply use temperature yet do not control temperature; if the temperature is too low decarboxylation will be incomplete, if temperatures are too high decarboxylated substances within cannabis will be lost to evaporation. Temperature control is therefore characteristic of a process that relies on temperature to decarboxylate. This is why the “uncontrolled” processes reviewed above that rely on temperature are truly uncontrolled.
Processes discussed above that use toxic solvents in “uncontrolled” ways rely on saturating available cannabis with the toxic solvent then filtering oil from plant parts.
The process sprays a solvent through a tube filled with a volume of cannabis as described in reference [18] implies that more or less solvent will be required will be required to remove all of the trichombes from available cannabis; even small variables, such as how the cannabis is prepared will affect the efficiency of the solvent's ability to reduce the cannabis uniformly.
For example as the raw cannabis material density varies per unit length of the tube, the solvent's efficiency of reducing cannabis will vary because butane evaporates very quickly; the process simply is not capable of controlling how much solvent contacts a given volume of cannabis before it evaporates; thus the process is uncontrolled in at least this one way.
Reference [19] Patent Application Publication US 2008/0241339, “Hemp Food Product Base and Processes”, by Mitchell et al. Publication Date Oct. 2, 2008. The reference heats hemp seeds in water and then mills or grinds the seeds, the seeds are then added into soups, beverages, and foods; the seeds are reported to have no Δ9-THC or medicinal cannabis. 
Recently, with the legalization of medical cannabis in 14 states, various edible cannabis products have become available; such products include cookies, biscuits, cooking oil, and dairy butter. These products are made without scientific controls by small producers because pharmaceutical companies do not produce edible cannabis products. Products like cookies or biscuits are eaten as is; products like cooling oil or dairy butter are usually added or cooked into other foods. Each one of these individual edible products have limitations the most significant one is uncontrolled dosage, cookies or biscuits contain cannabis fiber that often makes them green in color, and dairy products such as dairy butter spoil at room temperature.
A process for the production of a food grade intermediate product containing a known amount of medicinal cannabis is in controlled ways is the focus of the invention disclosed below.