Background art Sanitary toilet seat covers should provide a hygienic protection of the user of the public toilets in hotels, motels, at benzin tanks, in restrooms, in stadiums, in theatres and other cultural institutions. People fear, that using public toilet is connected with a risk of contracting a communicable disease and mistrust such equipments. Sanitary i. e. protective seat covers should eliminate the danger of transmitting infection. Such covers should prevent direct contact between the human butttocks and the toilet seat and protect thus the user against communicable deseases. The cover should in this way also diminish the fears od users of public washrooms. As the sanitary seat cover must provide a complete hygienic protection of the user, it must be of the contour and size to fit the toilet seat and must be made of suitable material. The cover should enable a simple and hygienic placing it into position and should be disposed of immediately after use. As this product is determined for a single use only it must not be expensive. These requirements are to a certain degree controversial and that is why the production of a suitable toilet seat cover represents a difficult problem.

The prior art toilet seat covers have usually the shape of a ring or of a sheet with central opening or slot, and some of them are provided with means, e. g. flaps for fixing the cover to the seat. Prior art concerning toilet seat covers include also covers with the central part in the shape of a cone, provided eventually with a central opening. The sanitary seat covers are produced usually of biodegradable plastic material or of paper. For hygienic reasons the cover should protect the user against direct contact of his skin with the surface of the seat and against diffusion of moisture from the seat. U. S. Patent No. 4,887.321 provides a toilet seat cover comprising a sheet of water-impermeable light weight paper coated on the reverse side which is adapted to face the toilet bowl with a water repellent material, the paper being provided with a single straight line longitudinal opening in the form of a slit, the cover being designed to be folded longitudinally along the slit and then transversely.

The cover has peripheral edges foldable under toilet seat before the use of the cover and is adapted to fit the toilet seat by the application of body pressure thereto. However the water repellent coating of the sheet and the necessity of folding the peripheral edges of the cover under the seat may be considered as disadvantageous features. The toilet seat cover should protect the user of the seat against infection. To solve this problem French patent application No. 87 10424 provides a toilet seat cover made of hygienic paper, the cover comprising a part adapted to fit the toilet seat and a part in the shape of a cone opening into the bowl of the toilet. U. S.

Patent No. 4,745.640 provides a matrix of cellulose fibers adhesively bonded together with an adhesive which is soluble or dispersible in water and contains a water soluble oxidizing agent and a water soluble ene- diol compound creating together a microbiocidal shield between the toilet seat and the skin of the user. Further requirements on the toilet seat cover concern its wholy covering the seat and its proper temporarily <BR> <BR> <BR> adhering to the seat. U. S. Patent No. 4,887.321 comprises peripheral edges of the toilet seat cover foldable under the seat. International patent application No. WO 88/01844 provides a sanitary cover for a toilet seat having means for its temporarily adhering to the seat, these means comprising adhesive patches at the center rear and forward sides of the cover or a continuous band of adhesive on the cover. French Patent Application No. 87 08220 provides a hygienic toilet seat cover comprising adhesive or elastic means in the form of two strips of adhesive on the opposite sides of the cover to fix it temporarily to the seat. International Patent Application WO 96/41563 provides a toilet seat cover comprising a foil of thin flexible folded material with folded edge which projects after the unpacking of the cover, the cover having two differently folded ranges of different tension. Another requirement relating to the toilet seat covers concerns an easy dissolution in water and a quick biodegradation of the cover. U. S. Patent No. 4,745.640 comprises a fibrous matrix a water soluble oxidising agent and a water soluble ene-diol compound microencapsulated within the cover wherein the capillary action of the fibrous matrix enables free water to disperse throughout the cover among ene-diol compound particles and particles of water soluble oxidizing agent, the cover being made of water disintegrateable material suitable for flushing down a toilet after the use thereof. The patent however does not provide means for fixing the cover onto the seat and some materials used therewith are not suitable for biodegradation. Prior art solutions are aimed mostly at one or two of the above specified problems and do not meet the requirements on the toilet seat covers as a whole. Some of them include materais insoluble in water, and some necessitate the user's manipulation with the toilet seat. Besides the production of most of these devices is complicated and expensive.

The object of the present invention is to provide a sanitary toilet seat cover which would fulfil simultaneously the sanitary, hygienic, environmental and technical requirements and the production of which would be cheap. The expression sanitary as used here means protective from the hygienic point of view.

Summary of the invention By the present invention a sanitary toilet seat cover is provided having the contour and the size of the toilet seat and having further peripheral edges preventing the contact of user's skin with the seat both on the inner and the outer side, comprising a disposable sheet consisting at least of two in water soluble layers, one of them made of cellulose fibers and one of them made of water receptive wax applied onto the fibrous layer e. g. by coating or by spraying, the sheet having a central part provided with a separating line on its periphery carried out by cutting or by perforation.

By another feature of the present invention the central part of the sheet is provided with circumferential perforation or by cutting only on three sides i. e. on both longitudinal sides and on the front side or on the rear side of the sheet or across the central part instead of the front or rear side.

By another feature of the invention the receptive wax layer has the form of a ring.

By another feature of this invention the cover contains microbiocidal means in some of the layers.

Preferably the fibrous layer is formed by a light weight paper of basis weight 15-40g/m2, made of usual paper raw materials, e. g. of chemical pulp, mechanical wood pulp or of waste paper pulp.

Preferably the layer of the water receptive wax is formed by wax on the base of water receptive polymers. In contact with the human body the layer of water receptive wax warms up and softens rapidly and consequently the cover adheres to the seat. On the other hand the layer of water receptive wax is homogeneous and protects the user sufficiently against bacteria. When flushed down the water receptive wax dissolves very quickly.

Adding microbiocidal means into the cover improves the hygiene of the milieu. It is advantageous especially when the layer of water receptive wax has a form of a ring only. The individual layers of the sheet may be of various thickness depending also on the way of storing the covers. With thin layers the bulk is substituted by the qualities of fibers used in the layer and by the qualities of water receptive wax. The perforation or the cutting on the periphery of the central part of the sheet should be preferably carried out on both longitudinal sides and on the front side or on the rear side of the central part, so that after placing the cover into position on the toilet seat the central part tilts down into the toilet bowl and contributes to fixing the cover in its position. The toilet seat covers are preferably produced on paper machines from a paper web wherein the individual covers are separated by perforation and can be then stored in webs, separated sheets or in the form of folded parcels.

The present invention enables to produce a high quality toilet seat cover which meets the requirements on such device entirely.

Brief Description of the Drawings In the accompanying drawings figure 1 shows a ground plan of the toilet seat cover and figure 2 represents a sectional view of the cover.

Description of Preferred embodiments Example 1: A sanitary toilet seat cover comprises sheet 1 consisting of fibrous layer 2 and of a layer of water receptive wax 3 applied on the fibrous layer 1 by spraying. The water receptive wax used in layer 3 is based on polyethyleneglycol HO- (CH2-CH2-O) n-CH2-CH2-OH, where n = 31.

The central part 4 of the sheet 1 is separated by cutting 5 discontinued on the front side 7 of the sheet 1. After detaching the central part 4 it remains connected with the cover on the front side 7 and contributes to fixing the cover in its position on the toilet seat. The described cover protects also the user of the toilet against moisture from the front part of the bowl.

Example 2: A sanitary toilet seat cover comprises sheet 1 consisting of a fibrous layer 2 of tissue paper of basis weight 17g/m2 and of a non-fibrous layer 3 represented by a water receptive polyolefine wax coated on the fibrous layer 2. The central part 4 of the sheet 1 is provided on its periphery with perforation 6 broken up on the rear side 8 of the sheet 1 Example 3: As the example 2, but the fibrous layer 2 is made of waste paper pulp of basis weight 25g/m2 and layer 3 coated on layer 2 has a form of a ring. The fibrous layer 2 contains microbiocidal means e. g. means with admixture of cloroxine or mupirocine. This embodiment requires less quantity of water receptive wax.

Example 4: As the example 2, but the layer 3 consists of water receptive industrial wax SP 07-259. The cetral part 4 is provided with perforation 6 on its both longitudinal sides 9 and across the central part in its half.

Industrial applicability The present invention will find a wide use in hotels, motels, in restrooms and in other public buildings.