JPH01148888A - Newspacer printing paper containing secondary fiber - Google Patents

Abstract

PURPOSE: To enable a secondary fiber such as waste paper to be recycled to newspaper printing process by segmenting it in a dry condition into fibers to finely grind ink particles included therein and then by directly mixing the fibers into a virgin pulp without the need of ink removing process. CONSTITUTION: A secondary fiber such as waste paper can be recycled as newspaper printing paper through such a process that, the secondary fiber such as waste paper is segmented substantially in a dry condition (with a moisture content of about 20 wt.%) to effect grinding ink particles included therein to a size of about <=20 μm, and the resulting segmented waste paper is directly mixed at about 20 wt.% into a virgin pulp without the need of ink removing process.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to newsprint paper manufactured using cellulose products containing ink, such as waste printing paper, as a secondary fiber source. It is.

BACKGROUND OF THE INVENTION Newsprint paper contains a relatively small amount of secondary fibers along with pure pulp produced by chemical or mechanical processes.

When using traditionally used secondary fibers, the first step is to remove ink from the secondary fibers in order to minimize unnecessary stains on the final newspaper print. is necessary. Naturally, this ink removal process increases the manufacturing price of newsprint. Additionally, many secondary fiber sources, including high-quality fibers, also contain paints such as inks and toners, which are difficult to remove by conventional wet deinking methods. Therefore, a secondary fiber source containing such high-quality fibers could not be used in the production of printing paper.

Therefore, in the production of newsprint, there is a need to be able to economically use secondary fiber sources, including those that are difficult to deink, and a desire to eliminate unnecessary stains and poor gloss. There is.

SUMMARY OF THE INVENTION The present invention relates to a novel newsprint material comprising substantially fragmented fibers produced by a mechanical fiberization process carried out in a substantially dry state and ink. Contains fine particles. The invention also relates to newsprint produced from such newsprint material.

The following unexpected fact was discovered by the present inventor. That is, when the secondary fibers are fiberized in a substantially dry state, the ink-containing particulates in the resulting newsprint material are so finely divided that they do not adversely affect the quality of the finished newsprint paper. It means that there is. Therefore, there is no need to separate ink from the ink-containing fine particles from other fibers, and the manufacturing cost can be significantly reduced, as well as the material cost.

Furthermore, based on the above points, it becomes possible to use inexpensive secondary fiber sources that could not be used in the production of newsprint because they cannot be deinked using conventional wet deinking methods. This allows further significant cost savings with the use of relatively inexpensive, high quality secondary fiber sources.

In the present invention, the ink particle size of the ink-containing fine particles obtained by the dry fiberization process is substantially within the range of about 70 microns or less (when converted to the diameter of a circular cross section). Desirably, all particles are less than or equal to about 100 microns, and even more desirably, all particles are less than or equal to about 150 microns. Ink particles larger than approximately 150 microns are perceptible to the naked eye when viewed from newspaper reading distance. On the other hand, particles with smaller diameters are effective in reducing gloss.

As used herein, "secondary fiber source" refers to cellulose products that contain ink, such as discarded printing paper, and that are recycled for use as a fiber source for papermaking. It means. Particularly useful secondary fiber sources include computer output paper, white ledger paper, and non-impact printed paper.

The term "substantially divided fibers" refers to fibers that have been virtually divided, the length of which is equal to or longer than the diameter, and a certain degree of agglomeration is formed.

"Substantially dry" means that the moisture content is about 20% or less,
This refers to a state in which the fibers and fine particles are sufficiently dry so that they do not adhere to each other during the fiberization process. In particular, it is preferable that the secondary fiber source be air-dried. This means that the secondary fiber source is at a moisture content that is in equilibrium with the atmosphere in which it is placed. Typically, this secondary fiber source will contain about 3-9% water by weight, which is approximately the range of water content for air-dried paper. Therefore, it is undesirable for excess moisture to be present or added to the secondary fiber source to be fiberized.

(Example) The present invention will be described in detail below with reference to the drawings.

First, with reference to FIG. 1, a fiberizing apparatus for fiberizing a secondary fiber source for use in the present invention will be described in detail.

FIG. 1 mainly shows the position of the rotor blades in the internal working chamber of the fiberizing device 1. As shown in FIG. Examples of such fiberizing devices are, for example, U.S. Pat. No. 3,069,10
It is stated in the specification of No. 3. The apparatus disclosed for implementing the invention is manufactured by Pallmann Re
f, 4 fiberizing device.

Reference numeral 8 is a serrated grooved operating surface, and with respect to this surface,
The feed material is rubbed by the action of moving rotor blades 9 driven by suitable drive means 2.

Cooling water is supplied to the fiberizer via an inlet boat 6 and an outlet port 7 to remove heat generation due to shearing of the feed fiber stock. Although it is not clear from FIG. 1, there is a spacing between the serrated working surface and the blade through which the cellulosic material is sheared. The blade position relative to the working surface 8 is adjustable, and this adjustment adjusts the degree of fiberization. This adjustment is also made by rotor speed, residence time, and the nature of the working surface. The working surface 8 consists of six removable segments. These segments can also be more or less segments with different surface shapes and configurations. Such flexibility allows endless options for optimizing and modifying the fiberization. Most importantly, the operational performance of the configuration described herein is extremely satisfactory. More specifically, the grooves of each segment shown are arranged parallel to each other and are approximately 2 mm open from apex to apex. Each groove is approximately 1.5 mm deep. The radial thickness of each segment is approximately 10 centimeters.

These dimensions are provided for illustrative purposes only and are not intended to be limiting. Also shown is a portion of the inner working surface of the hinged cover 10, which surface is of substantially the same construction as the other working surface 8 already described. By closing this cover, these two surfaces form an internal chamber for fiberizing the feed material.

FIG. 2 is a perspective view of the fiberizing apparatus with the rotor removed to expose the orifice 1). After passing through this orifice 1), the fiberized material is discharged from the outlet port 4. The diameter of this orifice is variable, and by adjusting it, the degree of fiberization is controlled by increasing or decreasing the air flow rate, and thus increasing or decreasing the dwell time within the fiberizer. The orifice is formed in a removable plate 12, making it easy to change the diameter of the orifice. For an orifice diameter of 160 mm, an air flow rate of approximately 10 cubic meters per minute has been found to be preferred. Also shown in FIG. 2 are the impeller blades 13 of the fan that provide the air flow through the fiberizer.

FIG. 3 is a cross-sectional view showing a part of the fiberizing device, showing an outline of the operation of the fiberizing device. The arrow is
Shows the direction of air and fiber flow. In detail, the secondary fiber source 15 is introduced into the feedstock 3 where it is brought into contact with the rotating blade 9 . With the air flow, the secondary fiber source is transferred to the rotor blades and the working surface 9.
The secondary fiber source is fragmented into gradually smaller particles. That is, the fibers are finely divided into substantially divided fibers and fine particles. The centrifugal force generated by the rotor blades forces particles, especially large particles, against the vertices between the inclined working surfaces. Such a pressing force avoids the possibility that larger particles will be ejected before they are completely fiberized. Orifice 1) of removable plate 12 after substantially complete fiberization
The finely divided solid particles are discharged through the . Furthermore, the fan impeller 13 forces the floating fibers through the outlet 4. The fibrous material, consisting of substantially fragmented fibers and particulates, can be collected and used as is as a feedstock for newsprint material in a conventional manner.

Next, the following individual embodiments will be described based on FIG.

A number of newsprint handsheets were made using different newsprint materials for the purpose of illustrating various forms of the invention. One of these newsprint materials is a material comprising substantially fragmented fibers and ink-containing particulates produced by substantially dry fiberization of a secondary fiber source as described above. The gloss (GE Brightness) of each of the obtained newsprint handsheets was measured.

This value is an indication of the amount and size of ink spots within the handsheet. The larger the measured value, the higher the reflectance and the higher the brightness. Sample 1 is a sheet made from a standard newsprint material containing (by dry weight) 32 parts semi-bleached kraft fibers, 68 parts groundwood fibers, and 7 parts clay filler (Zeolex®). ). Sample 2.3
The materials used in the production of Examples and 4 differ in the content of secondary fiber source materials (divided fibers and fine particles) that have been dried and fiberized according to the present invention. The material used in the production of Sample 5 contains a certain amount of a secondary fiber source that has been wet-fiberized by adding water so that the consistency is 3%. The secondary fiber sources used for samples 2 to 5 were:
1/3 of it is white copy ledger paper (manifold
white ledger), 1/3 is white ledger paper, and 1/3 is computer output paper printed using a non-impact method. In preparing each sample, each component of the material was slurried separately and then blended to a final solids consistency of 0.06% by weight. After this, handsheets were manufactured from this. Here, the production of this handsheet itself was carried out using the same conventional method.

GE Brightness Index
was determined by measuring the percent reflectance of blue light relative to a reference white surface. The instrument used for this measurement was rBrightimeter Model S4 B manufactured by Technidyne Corp.
rightmenss/ColorTe5terJ. For each sample, six measured values were totaled, and the average value of the total values was defined as the GE glossiness index.
.

A summary of the measurement results is shown in Table 1 below (the component amounts of the materials are shown in parts by dry weight).

As can be seen from these results, the gloss of the newsprint sheets produced according to the present invention is better compared to the samples produced using a wet fiberized secondary fiber source instead of dry fiberization. That is, the value is high (compare sample 2.3.4 and sample 5). Furthermore, the gloss values of the samples according to the invention are actually higher compared to the conditioned newsprint material. This is because the fibers from the secondary fiber source are of higher quality.

Non-impact printed computer output paper (CPO) with the aim of further demonstrating the benefits obtained by using dry fiberized secondary fiber sources.
Handsheets were made using 100χ as the single fiber source. In the production of sample 1), paper material was produced by wet fiberizing (slurrying) CPO paper. In the production of sample 12, a paper material was produced by drying CPO paper into fibers and then adding water to form a slurry. In both of these cases, no removal of ink-containing particulates caused by fiberization was performed.

Sample 1). After producing 12 handsheets and drying them - they were subjected to image analysis to measure the amount of ink spots appearing on their surface. 9 The area of spots larger than 5 microns was measured using an image analyzer. Then, based on the area, the diameter of the equivalent circle of each spot was calculated. As an image analyzer, the R Quanti manufactured by Cambridge is used.
met 720 J was used. In this analyzer, f4
Attached a 50mm EL-Niko port with a 70mm extensilan tube set to
Reflectance values of 40 or less were detected. Here, the value O is black (no reflection) and the value 64 is white (total reflection). The analyzer took measurements on 20 areas per sample. The area of each region is 7.5
It was set to mm x 5.75 mm.

The results of this image analysis are shown in Table 2 and FIG. 4. FIG. 4 plots the spot size distribution for each sample and shows a reduction in detectable ink spots in handsheets made in accordance with the present invention. As can be seen from the plot, the size of the ink particles contained in the handsheet made according to the present invention (Sample 12) ranges substantially below about 70 microns. Furthermore, as shown in Table 2, the average size of the spots,
Improvements are seen in terms of total spot area, number of detected spots, and glossiness.

As shown in Table 2 and Figure 4, by drying the secondary fiber source, very fine ink spots are formed and these spots cannot be detected. Paper produced from the material is not subject to any particular adverse effects. Also, the detectable ink spots are smaller and fewer in number than those seen in materials made by wet fiberization. Dry fiberization therefore provides a method in which a secondary fiber source can be used without deinking.

As will be appreciated by those skilled in the newsprint manufacturing industry, the embodiments described above are presented for illustrative purposes and are not intended to limit the scope of the invention thereto.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a fiberizing apparatus suitable for carrying out the method of the present invention, with the front lid removed to expose the impeller blades and serrated working surfaces. FIG. 2 is a cut away perspective view of an open fiberizer with the impeller blades removed to expose the orifice for removal of the fibers being processed from the working chamber; It is. FIG. 3 is a partially cutaway side view of the fiberizing device, showing its operating state. FIG. 4 is a graph obtained by plotting data from image analysis results, showing the particle size distribution of ink particles in two handsheets produced from computer output paper. Here, one of the two sheets is made from feedstock that has not been deinked by wet processing and the other is made from feedstock that has been dry fiberized in accordance with the present invention. 1 - Fiberization device 2 - Drive means 4 - Exit boat 6 - Artificial boat 7 - Outlet port 8 - Working surface 9 - Rotor blade 10 - Cover 1) - Orifice 12 -・Plate 13...-Impeller 15-...Secondary fiber source

Claims (7)

[Claims] (1) A newsprint material having substantially fragmented fibers and ink-containing particulates produced by mechanically fiberizing a secondary fiber source in a substantially dry state. (2) The material of claim 1, wherein at least 20 percent dry weight of fragmented fibers and ink-containing particulates are produced by mechanically fiberizing a secondary fiber source in a substantially dry state. A material characterized by containing. (3) In the material according to claim 1, the secondary fiber source is paper printed by a non-impact method;
A material characterized in that it is one of the group consisting of computer output paper, white ledger paper, and white ledger for copying. (4) A newspaper produced from a newsprint material having substantially fragmented fibers and ink-containing fine particles produced by mechanically fiberizing a secondary fiber source in a substantially dry state. printing paper. (5) The newsprint paper according to claim 4, wherein the size of the ink particles of the ink-containing fine particles is substantially within a range of about 70 microns or less. (6) The newsprint paper according to claim 4, wherein the size of the ink particles is about 100 microns or less. (7) The newsprint paper according to claim 4, wherein the ink particles have a size of about 150 microns or less.