JP2011026722A5 - - Google Patents

Description

As a result of diligent research to solve such problems, the present inventors have found that the fiber part is 2 to 10% by weight of synthetic fiber whose core part is polyethylene terephthalate and the sheath part is polyethylene terephthalate copolymer and 90 to 98% by weight of wood pulp. %, And a breathable decorative sheet base paper satisfying the following (1) to (3).
(1) Smoothness 150-300s
(2) Delamination 60 to 85 N / m
(3) Air permeability 10-16s
I will provide a.

When the freeness of wood pulp and synthetic fiber falls outside the range of 350 ml to 550 ml CSF, the balance between the air permeability and the beating degree is deteriorated. If the freeness is too low , the air permeability increases, and if the freeness is too high , the smoothness decreases and the printability deteriorates.

The basis weight of the obtained base paper is preferably paper-made so as to be 40 to 60 g / m ² . If it is less than 40 g / m ² , the air permeability is good, but it is not preferable because sufficient strength cannot be obtained. Also, undesirably breathability is deteriorated exceeds the 60 g / ^{m 2.}

The synthetic fiber used in the present invention is a synthetic fiber in which a core part is coated with a polyester resin and a sheath part is coated with a copolymer polyester resin having a lower melting point than the core part. The melting point of the polyester-based resin in the core is preferably 200 to 300 ° C., and the sheath is preferably about 100 to 150 ° C. By using a synthetic fiber having a melting point lower than that of the core portion for the sheath portion, the synthetic fiber in the sheath portion is dissolved on the paper surface by calendering to form a film, and the smoothness is improved to improve the printability. Further, since the core portion does not dissolve, air permeability can be secured.

Synthetic fiber used contains 2-10 by weight% of the total weight of the fiber content. Balance between a content breathable printability outside this range deteriorates. The synthetic fiber length used is 3-5 mm. A decorative sheet base paper having excellent printability can be obtained by using a synthetic fiber of 3 to 5 mm and having the above freeness. Moreover, the thickness of the synthetic fiber is 1.1 to 4.4 dtex. If the synthetic fiber has a thickness other than this, the balance between air permeability and printability is deteriorated.

(Examples 1 to 4) (Comparative Examples 1 to 5) Paper was made with a long net paper machine under the conditions shown in Table 1. Pulp is LBKP, synthetic fiber is core part: PET with melting point of 255 ° C, sheath part: PET copolymer with melting point of 110 ° C, 2.2 dtex, 3 mm long fiber is mixed with pulp, and double disc refiner is used in Table 1 Beat the freeness (Canadian) shown . Examples 1-4, Comparative Examples 4-5, carboxymethyl cellulose dry strength agent 0.25% by weight relative to the pulp, cationic starch surface paper strength agent 1.0% by weight, polyacrylic amide-epichlorohydrin resin 0.7% by weight of wet paper strength agent was added. In Comparative Examples 1-3, polyacrylic amide-epichlorohydrin resin wet paper strength agent 0.7 wt%, 1.3 wt% polyamide surface paper strength agent were added. The printed surface was brought into intimate contact with the Yankee dryer surface and dried, and was subjected to a calender treatment with a hot roll and linear pressure as shown in Table 1.

Claims (1)

As a fiber part, the core contains polyethylene terephthalate and the sheath contains polyethylene terephthalate copolymer in an amount of 2.0 to 10% by weight and wood pulp 90 to 98% by weight, and the following (1) to (3) Fills breathable decorative sheet base paper.
(1) Smoothness 150-300s
(2) Delamination 60 to 85 N / m
(3) Air permeability 10-16s