技术问题语段：
The technical problem addressed in this patent is the need for a protective article that can be easily removed and replaced, such as a napkin, to protect objects or parts of objects from damage or tarnishment. Existing solutions such as double-sided sticky tape or removable covers have limitations such as difficulty in application and increased cost. The invention provides a water-based adhesive that allows the sheet to be non-permanently adhered to an object, making it easier to protect objects while also being more cost-effective.
技术功效语段：
The use of a water-based adhesive in manufacturing protective articles has several advantages. It is safe for users and does not harm or irritate the skin. Additionally, the adhesive can be quickly dried using a controllable heat source, such as an IR lamp, to maximize manufacturing efficiency.
权利要求：
1. A protective article comprising: a sheet having a first surface; and an adhesive portion arranged on a first portion of the first surface; wherein the sheet is folded such that the first portion of the first surface faces a second portion of the first surface, thereby bringing the adhesive portion into engagement with an adhesive-free portion of the second portion of the first surface, the adhesive being of a type that will allow the adhesive portion to separate from the second portion of the first surface and allow the sheet to be adhered to an object.
2. A protective article according to claim 1, wherein the adhesive portion is sprayed, rolled, printed or stamped on to the first surface of the sheet.
3. A protective article according to claim 1 or claim 2, wherein the adhesive portion has a polygonal shape or a curvilinear shape having one or more curved sides and/or wherein the adhesive portion has the form of an elongate strip, optionally wherein at least a portion of the elongate strip is straight, zig-zagged, curved or wavy.
4. A protective article according to any one of the preceding claims, wherein the adhesive is coloured by the addition of one or more colouring agents, dyes and/or pigments.
5. A protective article according to any one of the preceding claims, wherein the sheet is folded prior to application of adhesive and/or wherein the sheet is folded more than once.
6. A protective article according to any one of the preceding claims, wherein one or more adhesive portions are arranged on a second surface of the sheet.
7. A protective article according to any one of the preceding claims, wherein the sheet is made from card, cloth, woven fabric, non-woven fabric, plastic, or single or multiple plies of paper.
8. A protective article according to any one of the preceding claims, wherein the adhesive comprises a water-based adhesive.
9. A protective article according to any one of the preceding claims, wherein the protective article comprises a napkin, a dental napkin, a napkin for medical use, a surgical napkin, an apron, a bib, a table cloth, a coaster, a place mat, a furniture cover for indoor or outdoor use or a windscreen cover for a vehicle.
10. An apparatus for applying adhesive to a sheet comprising: an adhesive applying means operable to spray, roll, print or stamp a water-based adhesive on to a first surface of the sheet, so as to provide at least one adhesive portion on the first surface of the sheet, the water-based adhesive allowing, in use, the sheet to be non-permanently adhered to an object.
11. An apparatus according to claim 10, wherein the adhesive applying means is operable to vary, e.g. in accordance with a predetermined program or on demand from an operator, the rate of applying of the water-based adhesive and/or the properties, e.g. chemistry, composition and/or colour, of the water-based adhesive.
12. An apparatus according to claim 10 or claim 11 comprising a sheet delivery means configured to place the sheet so as to present the first surface of the sheet to the adhesive applying means and/or comprising one of more folding means for folding the sheet along a fold.
13. An apparatus according to any one of claims 10 to 12 comprising a drying means arranged to dry the adhesive portion(s) on the first surface, optionally wherein the drying means comprises a heat source, further optionally wherein the heat source is controllable to vary the drying rate.
14. An apparatus according to any one of claims 10 to 13 comprising cutting means for cutting the sheet of material and/or comprising an embossing means, a printing means and/or a stamping means for imparting a surface texture or decoration to the sheet.
15. An apparatus for manufacturing a protective article or a manufacturing line comprising an apparatus according to any one of claims 10 to 14.