Methods and apparatuses for applying coatings on a baggy web are provided. A Mayer rod and a back-up roll engage with each other to form a nip. The back-up roll has a deformable inner layer with a surface thereof covered by a deformable outer layer. The Mayer rod and the flexible web at a contacting area are impressed into the back-up roll with a machine-direction nip width W and a nip engagement depth D, which enables formation of a coating having a substantially uniform thickness.

Methods and apparatuses for applying coatings on a baggy web are provided. A Mayer rod and a back-up roll engage with each other to form a nip. The back-up roll has a deformable inner layer with a surface thereof covered by a deformable outer layer. The Mayer rod and the flexible web at a contacting area are impressed into the back-up roll with a machine-direction nip width W and a nip engagement depth D, which enables formation of a coating having a substantially uniform thickness.

The invention relates to a roll for use in a manufacture of a fibrous web, which comprises cellulosic fibers. The roll comprises a roll body with a cylindrical surface, and a roll cover, which is arranged to cover the cylindrical surface of the roll body. The cover has a functional layer, which has a polymer matrix and reinforcing material in the form of functional particles and/or functional fibers embedded in the polymer matrix. The functional particles and/or functional fibers has nanocellulose material. The invention relates also to the use of the roll.

The invention relates to a roll for use in a manufacture of a fibrous web, which comprises cellulosic fibers. The roll comprises a roll body with a cylindrical surface, and a roll cover, which is arranged to cover the cylindrical surface of the roll body. The cover has a functional layer, which has a polymer matrix and reinforcing material in the form of functional particles and/or functional fibers embedded in the polymer matrix. The functional particles and/or functional fibers has nanocellulose material. The invention relates also to the use of the roll.

A process for acylation of a solid material (3, 9) bearing reactogenic hydroxyls includes at least one fatty acid chloride (1) is distributed at least on the surface of the solid material (3, 9) using a distributor device (2) having an application surface. At least one fatty acid chloride (1) is distributed at least on the surface of the solid material (3, 9) is heated at a temperature, referred to as acylation temperature, below the vaporization temperature of the at least one fatty acid chloride (1), so as to enable an acylation of the solid material (3, 9). A stream of a gaseous composition (6) is directed over the said solid material (3, 9) at the acylation temperature, so as to entrain at least one portion of gaseous hydrochloric acid (7) formed by the acylation reaction

The application surface of the distributor device (2) is a velvet provided with velvet filiform elements that are suitable for taking up the at least one fatty acid chloride (1) by contact with the at least one fatty acid chloride, and releasing at least one fatty acid chloride by bringing the filiform elements of the velvet into contact with the solid material (3, 9). The distribution step (12, 14) is carried out so as to distribute over the solid material (3, 9) an amount of the at least one fatty acid chloride (1) of between 20 mg/m.sup.2 and 1 g/m.sup.2 surface area of the solid material (3, 9).

A method and a device for the application of starch on a moving fiber web, especially on a packaging paper web such as a testliner or a corrugated medium web, include first applying starch to a first roll and/or a second roll and passing the fiber web through a treatment nip formed by the first roll and the second roll. At least one of the first or the second roll, preferably both rolls, have a hardness of 15 P&J (Pusey & Jones) or lower, preferably 5 P&J or lower and most preferably 1 P&J or lower. The starch is applied to the first roll and/or the second roll by a slot die and/or a slide die and then transferred to the fiber web in the treatment nip.

Methods and apparatuses for applying coatings on a moving web are provided. A slot die including a concave die lip coating surface and a back-up roll engage with each other. The back-up roll has a deformable inner layer with a surface thereof covered by a deformable outer layer. The slot die and the flexible web at a contacting area are impressed into the back-up roll with an engagement depth D, which enables formation of a coating having a substantially uniform thickness.

Methods and apparatuses for applying coatings on a moving web are provided. A slot die including a concave die lip coating surface and a back-up roll engage with each other. The back-up roll has a deformable inner layer with a surface thereof covered by a deformable outer layer. The slot die and the flexible web at a contacting area are impressed into the back-up roll with an engagement depth D, which enables formation of a coating having a substantially uniform thickness.

An apparatus for producing a web of fibrous material includes a roll having incisions with a depth of 0.01-2.00 mm, a width of 0.01-2.00 mm, and a pitch 0.01-10.00 mm, and rotated at a peripheral velocity v.sub.1 equal to the velocity of an upstream apparatus unit; a belt stretched between transmission rollers that advances at a velocity v.sub.2 less than v.sub.1, wherein v.sub.1/v.sub.2 lies between 1.05 and 1.40; a presser roller rotating at a peripheral velocity v.sub.2, associated with a presser system acting to press the belt against the metal roll with a pressure of 1-200 kg per centimeter; and a system that feeds a sheet of pliable fibrous material between the belt and the roll, the belt having a longitudinal elongation of no more than 5%, dimensional stability along its entire length, a thickness of 1-10 cm, and a hardness 24-70° Shore A.

A method and a device for the application of starch on a moving fiber web, especially on a packaging paper web such as a testliner or a corrugated medium web, include first applying starch to a first roll and/or a second roll and passing the fiber web through a treatment nip formed by the first roll and the second roll. At least one of the first or the second roll, preferably both rolls, have a hardness of 15 P&J (Pusey & Jones) or lower, preferably 5 P&J or lower and most preferably 1 P&J or lower. The starch is applied to the first roll and/or the second roll by a slot die and/or a slide die and then transferred to the fiber web in the treatment nip.