The invention relates to a water-free alcohol disinfectant capable of destroying spores. Preferably, the disinfectant also contains an additional chemical sterilization agent, e.g., hydrogen peroxide, in very low concentrations within the range of between 0.5 and 3.0 percent of the weight of the alcohol solution. The disinfectant is usable in industrial contexts for bacteriological cleaning of surfaces, for example, inner walls in pipelines, conduits, reaction vessels, and other process equipment, without corroding or chemically attacking the material in such surfaces.

TECHNICAL FIELD
 The present invention relates to a disinfectant containing a solution of
 alcohol. The invention also relates to a method of producing the
 disinfectant, and use of an alcohol solution containing hydrogen peroxide
 in a quantity of between 0.3 and 3.0 per cent for destroying spores and
 similar micro-organisms.
 BACKGROUND ART
 Alcohol disinfectants are known from, for example, EP-A-O 016 319 which
 describes such an agent for cleaning wounds and similar practical
 applications. The prior art disinfectant contains a solution of alcohol to
 which has been added, for purposes of stabilisation, hydrogen peroxide in
 an amount of between 0.05 and 1 per cent of the weight of the alcohol
 solution. According to EP-A-O 016 319, it is possible, by means of this
 addition of hydrogen peroxide, to prevent the uncontrolled growth of
 spores and the like unintentionally introduced into the disinfectant. A
 disinfectant similar to that described above is also known from EP-A-O 252
 278 which proposes, also for purposes of stabilisation, the addition of
 hydrogen peroxide so as to prevent the uncontrolled growth of spores and
 similar micro-organisms and thereby stabilise the alcohol disinfectant.
 In addition to wound treatment and skin cleaning purposes, disinfectants
 are also employed in industrial contexts for destroying undesired
 (pathogenic) bacteria and other harmful micro-organisms. In, for example,
 the food and pharmaceuticals industries, extremely high demands on hygiene
 are often placed on the produced product, partly in order that the product
 can be consumed at all, and partly to enable it to be packed and stored
 without the risk of being destroyed during its storage life as a result of
 decomposition reactions occasioned by micro-organisms and/or the
 uninhibited/uncontrolled growth of harmful micro-organisms which may
 unintentionally accompany the product into its package.
 In order to satisfy the demands on product hygiene, it is therefore not
 least important that the equipment which is used for producing and
 packaging the product be carefully monitored and controlled and, if
 necessary or as a preventive measure, be regularly cleaned and disinfected
 so as to eliminate the presence of harmful micro-organisms in the
 immediate vicinity of the product. It is of particular importance that
 such surfaces (for example pipelines, conduits and the like) which the
 product flows in direct contact with, or otherwise comes into direct
 contact with during the producing and packing processes are kept
 hygienically clean and free of micro-organisms which risk harming the
 product. This naturally also applies to the package and the material from
 which the package is produced.
 For disinfecting and cleaning equipment employed in industrial processes of
 the type described above, it is known in the art to use solutions of
 alcohol, such as ethanol and/or propanol. These known agents are active
 against such micro-organisms as vegetative bacteria, fungi and viruses
 which may therefore readily be eliminated, but are incapable of combating
 spores.
 Another known disinfectant and cleaning agent for industrial applications
 is based on chemicals such as peracetic acid, hydrogen peroxide,
 formaldehyde and glutaraldehyde which are all highly active against not
 only micro-organisms such as vegetative bacteria, fungi and viruses, but
 also against spores which may thus readily be eliminated by treatment with
 these known agents. One problem however is that the these sporicidal
 agents are highly corrosive and, as a result, also attack and destroy the
 material, for example stainless steel, plastic, rubber etc., employed in
 conventional process equipment.
 There is thus a need in the art for a disinfectant for industrial use which
 may efficiently be employed for eliminating micro-organisms, including
 spores, but which at the same time does not attack and destroy the
 material, for example non-stainless steel, plastic, rubber etc., in those
 surfaces from which the micro-organisms are to be eliminated.

OBJECT OF THE INVENTION
 One object of the present invention is therefore to realise a disinfectant
 of the type described by way of introduction which makes for an efficient
 destruction of undesired micro-organisms, including spores, without
 chemically attacking the material in those surfaces from which the
 micro-organisms are to be eliminated.
 SOLUTION
 This object is attained according to the present invention in that a
 disinfectant of the type described by way of introduction has been given
 the characterising feature that the alcohol solution employed is
 practically water-free.
 The term "practically water-free" used in this description and in the
 appended Claims is here taken to signify an alcohol solution which, while
 not being completely free of water, contains such a slight quantity of
 water as it possibly can in order that the object according to the
 invention be attained. It will be obvious to the skilled reader of this
 specification that absolutely water-free alcohol solutions seldom exist in
 practice, since such alcohol solutions are--primarily for technical and
 economical reasons--difficult or economically indefensible to produce,
 given the applications for which such alcohol solutions are often
 intended. Consequently, the expression "practically water-free" in this
 context implies an alcohol solution which has so little water as is
 warranted for both production-engineering and economical reasons without
 jeopardising the object according to the present invention. In order
 further to clarify and concretise the implications of this expression, it
 should be added that alcohol solutions of different alcohols contain, or
 may contain, different quantities of water without departing from the
 spirit and scope of the inventive concept as herein disclosed. For
 example, an alcohol solution of ethanol may contain water in quantities of
 up to approx. 4 per cent, i.e. be a 96 per cent ethanol solution, while an
 alcohol solution containing propanol (n-propanol and/or isopropanol) may
 contain water in quantities corresponding to approx. 30 per cent of the
 weight of the alcohol solution, i.e. be a 70 per cent propanol solution.
 The disinfectant according to the invention which is, like the prior art
 disinfectants according to the above disclosed publications EP-A-O 016 319
 and EP-A-O 252 278, based on an alcohol solution thus differs from these
 prior art disinfectants in that the alcohol solution employed is to
 contain a reduced quantity of water or be practically water-free in the
 meaning and scope as apparent from the foregoing discussion.
 According to the invention, it has surprisingly proved that a disinfectant
 which is based on an alcohol solution which is practically water-free
 makes for efficient destruction of micro-organisms, not only of the type
 such as vegetative bacteria, fungi and viruses, but also of spores, which
 have previously proved to be difficult or impossible to eliminate using
 prior art alcohol-based disinfectants.
 The disinfectant according to the present invention has further proved to
 be an efficient cleaning agent in industrial applications for eliminating
 such micro-organisms, including spores, from the inner walls in pipelines,
 conduits, reaction vessels and similar process equipment, without
 chemically attacking or causing corrosion in the material which is used in
 such apparatuses.
 According to one preferred embodiment of the present invention, the
 disinfectant also includes an additional chemical destruction agent of the
 above-described sporicidal, but corrosive type, such as peracetic acid,
 hydrogen peroxide, formaldehyde and glutaraldehyde. In such instance, it
 has surprisingly proved that the corrosive effect of such agents may be
 considerably reduced and even entirely eradicated while retaining
 sporicidal activity, even at very low concentrations of this agent. Such a
 "synergistic" effect is attained according to the present invention even
 at such low concentrations as between approx. 0.5 and 3.0 per cent which
 is the preferred concentration range for this agent when employed in the
 disinfectant according to the preferred embodiment of the invention.
 Such a particularly preferred additional chemical destruction agent
 according to the invention is hydrogen peroxide in concentrations of
 between 0.5 and 3.0 per cent of the weight of a water-free alcohol
 solution.
 Further advantageous and expedient embodiments of the disinfectant
 according to the present invention have moreover been given the
 characterising features as set forth in the appended subclaims.
 The present invention will now be described in greater detail hereinbelow,
 with the aid of a non-restrictive practical embodiment in which the
 elimination efficiency of the disinfectant according to the present
 invention is illuminated.
 To a water-free solution containing either propanol (n-propanol and/or
 isopropanol) or ethanol, hydrogen peroxide (H.sub.2 O.sub.2) was added in
 quantities corresponding to between 0.5 and 3.0 per cent of the weight of
 the solution. A surface (metal, plastic) was inoculated with a hydrogen
 peroxide resistant spore suspension of Bacillus subtilis A (BSA 22),
 whereafter the inoculated surface was sprayed with a) water as control
 reference and b) one of the above-produced disinfectants according to the
 invention. After 15 min., the spore reduction effects of the different
 solutions (disinfectants) was determined by washing of the surfaces with
 swabs, preparation of test dilutions, and plating on PC agar.
 The results showed that hydrogen peroxide in water had a very low reduction
 effect on the spores (within the range of 1 log) as compared with the
 control reference (the water), but that this effect increased within the
 concentration range of between 0.3 and 5.0 per cent. On the other hand,
 hydrogen peroxide in combination with the water-free solution of propanol
 (iso-propanol and/or n-propanol) or ethanol displayed a very good
 (synergistic) reduction effect between log 5 and log 6 with BSA spores in
 the concentration range of between 0.5 and 1.0 per cent.
 It is thus apparent from the results of the described Example that the
 disinfectant according to the invention is a valuable chemical
 disinfectant possessing surprisingly good destruction effects also
 vis-a-vis spores. The disinfectant according to the present invention is
 particularly well-suited as bacteriological and sporicidal cleaning agent
 also in industrial contexts for cleaning surfaces of plastic, metal and
 rubber without corroding or otherwise attacking and destroying such
 surfaces. The disinfectant according to the invention is moreover easy to
 produce by a simple mixing process.
 It should finally be observed that the above description is not intended to
 limit the present invention, various modifications and variations being
 possible without departing from the spirit and scope of the inventive
 concept as this is defined by the appended Claims. Such modifications and
 variations are, however, evident and obvious to a person skilled in the
 art and are thus intended to be encompassed by the scope of the appended
 Claims.