JPS62225342A - Manufacture of resin reinforced paper core - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a resin-reinforced 4-/#- core useful as a core material for 74 flannel for partition walls, doors, floors, etc.

[Conventional technology]

Conventionally, compressive strength in normal and wet conditions has been required for core materials for partition walls, doors, floors, etc., especially for new building materials, and in order to meet these requirements, various types of resins have been impregnated.・It has been hardened and strengthened. This strengthening method can be roughly divided into two types; one is 1. Adhesive application process (process of drawing adhesive lines on the base paper at regular intervals), 26-layer adhesion process (process of stacking and adhering the base papers with adhesive lines drawn on them alternately), 3. Cutting Process (process of cutting into predetermined dimensions to make bar-shaped stacked laminate paper), 4. 5. Expanding process (mainly forming into a nicam shape with many through holes inside); 5. Resin liquid impregnation step ()/Step of impregnating a nicum-shaped object with resin liquid, etc.), 6. This is a manufacturing method that consists of six steps: a heat treatment step (a heat treatment step for the purpose of hardening and/or drying the resin), and the other is manufactured through the same process described above using a roll-up base paper that has been pre-impregnated with a resin liquid. However, although the above-mentioned "5. Resin liquid impregnation step" is omitted,
It also consists of six steps (see Figure 1). In this case, the former method has poor workability, especially in the impregnation process, and the latter method uses the roll-up base paper that has been pre-impregnated with resin liquid, so the above-mentioned "5. Resin liquid impregnation process" is omitted. Since the process of making the impregnated base paper and the subsequent process are separated, there are problems such as poor consistency in production. Furthermore, conventional impregnating resins for both methods are hardened and/or
Otherwise, a heat treatment process for drying solvents is required, and no method has been found for manufacturing resin-reinforced waves or cores that satisfies customers' strict demands for cost performance in terms of performance, cost, lightness, thickness, and size. It wasn't.

[Problem that the invention seeks to solve]

In view of the above-mentioned situation, the inventors of the present invention have conducted intensive studies on the production of 1-percore in order to improve cost performance in terms of performance, cost, light weight, shortness, and smallness.The inventors of the present invention impregnated base paper with a specific amount of isocyanate compound and immediately applied the adhesive. It has been discovered that when Epercore is manufactured by laminating, adhering, stretching and curing using the same, the compressive strength in normal and wet conditions is significantly improved, and the method of the present invention has been achieved.

[Means for solving problems]

That is, in the method of the present invention, after impregnating base paper with an isocyanate compound having two or more isocyanate groups in the molecule using a dipping roll, roll coater, flow coater, spray coater, etc., the excess present on the surface of the base paper is removed. If there is an isocyanate compound, squeeze it with a squeezing roll,
By removing it with a doctor fray etc., it is impregnated to a saturated impregnation amount of 8% or more per unit weight of the base paper, and immediately using a known water-soluble polymer and/or water-based resin emulsion as an adhesive, from the adhesive at regular intervals. The isocyanate compound-impregnated base paper is characterized by drawing multiple lines of a certain width, and after stacking and adhering by alternately shifting the base paper, the isocyanate compound-impregnated base paper is expanded and cured within a time period that allows it to be expanded (usually hardened during the stock period). (See Figure 1).

[For production]

It has been found that the compressive strength of the Ni-G core produced by the method of the present invention is significantly improved when the base paper is cured with the isocyanate compound used in the present invention sufficiently impregnated inside the base paper. That is, isocyanate compounds constitute the base paper? Penetrates into the micro voids between fibers,
It reacts with the hydroxyl groups of cellulose, which is the main component of pulp fibers, and the water contained in the base paper, reinforcing the pulp fibers through crosslinking, and this effect contributes to improving the compressive strength in normal and wet conditions. it is conceivable that. Furthermore, since this reaction proceeds at room temperature, there is no need for heat treatment, and by installing an appropriate impregnation device in front of the existing adhesive application device, the process of impregnating the isocyanate compound and applying the adhesive can be completed. This eliminates the need for the inefficient impregnation process and heat treatment process that were essential in conventional methods, greatly improving workability and resulting in significant improvements in cost and performance.

The isocyanate compound used in the present invention means a compound having at least two or more isocyanate groups in the molecule, such as tolylene diinocyanate, 4.4'-
Diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, tri.

Non-diisocyanate, xylylene diisocyanate,
p-phenylene noisocyanate, tetramethylxylene diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate, 4.4'-
Aromatics such as dicyclohexylmethane diisocyanate, lysine soisocyanate, p-cyclohexylene diisocyanate, tetramethylene diisocyanate,
Aliphatic and cycloaliphatic diisocyanate compounds, triphenylmethanetriinocyanate, tris(isocyanatephenyl)thiophosphate, 1,6,11-undecatriisocyanate), 1,8-diisocyanate-4
- Aromatic, aliphatic and heterocyclic triisocyanate compounds such as isocyanate methyl octane, synester triisocyanate, 1,3,6-hexamethylene triisocyanate, bicyclohebutane triisocyanate; isocyanate 2
mer or 3i monomer. Also, polyester polyols, polyether polyols, epoxy polyols, acrylic polyols, polyptasoene polyols
and low molecular weight polymers such as isocyanate-modified products of phenolic polyols and polymethylene polyphenylisocyanate. Furthermore, allophanate modified products and biuret modified products of the above-mentioned isocyanate compounds may be mentioned. Note that these isocyanate compounds may be used alone or in combination. Among these, polymethylene polyphenylisocyanate and 4,4'-diphenylmethane diisocyanate are preferably used.

In the step of impregnating base paper with such an isocyanate compound to produce a honeycomb structure, and then curing the impregnated ino7anate compound, if it is desired to adjust the reaction rate of the isocyanate compound for practical purposes, organometallic It is necessary to use a catalyst such as a tertiary amine type or a tertiary amine type catalyst.

Furthermore, when trying to improve the impregnation of the isocyanate compound into the base paper and also improve the strength and durability of the resin-reinforced R-Zo-core, in addition to adding a catalyst to the isocyanate compound, solvents and plasticizers may be added. , antioxidants, hydrolysis inhibitors, insect repellents, etc. may be used alone or in combination.

The water-soluble polymer and/or water-based resin emulsion used in the adhesive in the present invention refers to the following substances or compositions, and examples of water-soluble polymers include polyvinyl alcohol and its modified products, polyacrylamide, and Modified products thereof, cellulose derivatives (carboxymethylcellulose, methylcellulose, hydroxyethylcellulose), starch and its derivatives (dextrin, aldehyde starch), sodium alginate, glue, gelatin, casein,
Examples include water-soluble natural or synthetic polymers such as gum tragacanth and gum arabic, and modified products (or derivatives) thereof, and inorganic compounds such as water-soluble polymers. An example of an aqueous resin emulsion is vinyl acetate (abbreviated as VAc).
VAc-(meth)acrylic acid ester system, VAc
-Ethylene-based, VAc-Vinyl versatate-based, vA
Aqueous synthetic resin emulsions such as vinyl c-globionate, (meth)acrylic ester, (meth)acrylic ester-styrene, styrene-butadiene,
Examples include synthetic rubber latex such as acrylonitrile-butadiene type, methacrylic acid ester-butatsuene type, and chloro o7'v7 type, as well as natural rubber latex. Among them, in consideration of cost/workability/performance, vinyl acetate resin or VAc-ethylene copolymer emulsion using polyvinyl alcohol as a membrane-retaining colloid is preferably used. Furthermore, it improves workability and adhesion when base papers impregnated with isocyanate compounds are laminated and bonded with an adhesive, and then expanded to form a nicum-shaped article with many through holes. 11 for resin reinforcement? - When trying to improve the durability of the core, use solvents, plasticizers, fillers, thickeners, penetrants, antifoaming agents, fungicides, insect repellents, etc. alone or in combination with the adhesives mentioned above. You may.

Next, the amount of impregnation of the isocyanate compound used in the present invention and the amount of application of the water-soluble polymer and/or aqueous resin emulsion used as the adhesive will be explained. The amount of isocyanate compound impregnated is 8% by weight per unit weight of the base paper used (for example, the amount of impregnation in a base paper of 16,097 m2 is 1% by weight)
The upper limit is the saturated impregnation amount of the isocyanate compound used, preferably 15% by weight (for example, the impregnation amount with a base paper of 1601 m2/m2 is 24, li' /m2...immediately after impregnation), the upper limit is the saturated impregnated amount.

In other words, if the amount of isocyanate compound impregnated is less than 8% by weight per unit weight of the base paper, no significant improvement in the compressive strength under normal conditions or wet conditions can be expected, as shown in Examples and Comparative Examples. If this amount is exceeded, excess of the compound will cover the surface of the base paper, and the surface chemical "wetting" of the adhesive will deteriorate, making it difficult not only to apply the adhesive uniformly, but also to reduce the initial adhesion. There may be a shortage. The coating amount of the water-soluble polymer and/or water-based resin emulsion used as the adhesive is 10 to 100 g/rrL2, preferably 30 to 100 g/rrL2, calculated in terms of the area of the adhesive actually applied to the base paper.
70 g/m2, and if it is less than 10 g/m2, the effective adhesive area will decrease due to insufficient amount of adhesive applied, resulting in poor adhesion, whereas if it is more than 100 g/m2, there will be too much moisture in the adhesive. The poor initial adhesion caused by this may lead to a decrease in workability, and furthermore, the extrusion of the adhesive may reduce the dimensional accuracy of the completed Taku-e-core.

〔Example〕

Next, the present invention will be explained with reference to Examples and Comparative Examples.

The isocyanate compounds used in the present invention, 2rimethylene polyphenyl isocyanate and 4,4'-diphenylmethane diisocyanate, are manufactured by Kasei Azzonoyon Co., Ltd.
products, PAPI-135 and l5ON, respectively.
ATE-143L, and the adhesive is vinyl acetate resin emulsion (Polysol adhesive 1011: Showa Kobunshi Co., Ltd.)
The base paper used is A-grade medium core base paper (product size:
16011/m2, density: 0.5317cm3). In addition, the compressive strength of Benog core is measured by JISA.
6931.

Example 1 A base paper cut to a predetermined size is impregnated with polymethylene polyphenylinocyanate using a dipping roll, and after removing the excess isocyanate compound present on the surface of the base paper using a squeezing roll, a plurality of lines of a constant width are immediately formed. was drawn using an adhesive, the base papers were alternately shifted, stacked and bonded, pressed for several minutes, and then decompressed, stretched to form a honeycomb shape, and then cured at room temperature.

In this case, the impregnation rate of the isocyanate compound was 37% by weight per unit weight of the base paper.

Example 2 4 was carried out in the same manner as in Example 1 except that the impregnation time of polymethylene polyphenylisocyanate was relatively shortened.
-/#- core was produced.

The impregnation rate of the isocyanate compound in this case was 15% by weight per unit weight of the base paper.

Example 3 Instead of polymethylene polyphenylisocyanate, 4
．． A core was prepared in the same manner as in Example 1 except that 4'-diphenylmethane diisocyanate was used.

In this case, the impregnation rate of the isocyanate compound was 59% by weight per unit weight of the base paper.

Example 4 4, instead of polymethylene polyphenylisocyanate
A 4-no and one core was prepared in the same manner as in Example 1, except that 4'-diphenylmethane diisocyanate was used and the impregnation time with the isocyanate compound was relatively shortened.

The impregnation rate of the isocyanate compound in this case was 32% by weight per unit weight of the base paper.

Comparative Example 1 (Isocyanate compound untreated) A plurality of lines of a constant width were drawn using adhesive on a base paper cut to a predetermined size, the base paper was alternately shifted and stacked, and after being pressed for several minutes, it was released. It was pressed and stretched to form a honeycomb shape, and then dried at room temperature.

Comparative Example 2 After applying polymethylene polyphenylisocyanate to a base paper cut to a predetermined size using a spray coater, immediately draw multiple lines of a constant width using an adhesive, then shift the base paper alternately and apply weight. The sheets were stacked and bonded, pressed for several minutes, decompressed, stretched to form a honeycomb shape, and then cured at room temperature. In this case, the impregnation rate of the isocyanate compound was 5% by weight per unit weight of the base paper.

The results of the above Examples and Comparative Examples are summarized in Table 1.

(See the margins below) [Effects of the Invention] According to the method of the present invention, the conventional step of impregnating base paper with a reinforcing resin liquid is greatly simplified, and a heat treatment step is not required, making it possible to streamline the work process and save energy. , and the compressive strength under normal conditions and when resistant to moisture is improved.
It is possible to improve cost and performance based on performance/cost/lightness, weight, and shortness.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the manufacturing process of E-G Core,
The upper row is a process diagram of conventional method No. 1, the middle row is a process diagram of conventional method No. 2, and the lower row is a process diagram of the method of the present invention.

Claims (1)

[Claims] Add 8% by weight of an isocyanate compound having two or more isocyanate groups in the molecule to the base paper per unit weight of the base paper.
After impregnating to the above saturated impregnation amount, multiple lines are drawn at regular intervals using a water-soluble polymer and/or water-based resin emulsion as an adhesive, and the isocyanate compound-impregnated base paper is spreadable by stacking and adhering the lines by alternately shifting them. Within a certain period of time,
A method for producing a resin-reinforced paper core characterized by stretching and curing.