JPH0454000B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a flame-retardant paper used as a lining paper for vinyl chloride wallpaper (hereinafter referred to as vinyl wallpaper). This invention relates to a backing paper for wallpaper that has a vinyl paste layer that does not easily swell and has excellent processability. [Prior Art] Flame retardant paper is used as a lining paper for various types of wallpaper. There are various types of wallpaper, including vinyl wallpaper, woven wallpaper, and paper wallpaper, but in Japan, vinyl wallpaper occupies the majority. Here, vinyl wallpaper is manufactured by coating vinyl paste on the surface of a backing paper, gelling it, and then going through processes such as printing, foaming, and embossing. In particular, in the gelling step, it is desired to be able to gel at as high a temperature and speed as possible from the viewpoint of efficiency. However, the higher the temperature becomes, the more likely it is that blistering will occur between the backing paper and the vinyl layer due to the influence of volatile components such as solvents and plasticizers in the vinyl paste. In other words, blisters are more likely to occur. This blistering is undesirable as it causes deterioration in printability and appearance and significantly reduces commercial value. In order to improve productivity, it is necessary to gel at high temperatures,
It is necessary to increase the processing speed as much as possible. For this reason, there is a need for a flame-retardant backing paper for vinyl wallpaper that does not cause blisters in the vinyl layer even at high temperatures and is less likely to cause blisters. [Problems to be Solved by the Invention] The present invention provides a backing paper for vinyl wallpaper that is difficult to use for vinyl wallpaper and has excellent processing efficiency, which prevents the vinyl layer from blistering or blistering even at high temperatures when the vinyl paste gels. This is where you get the flammable backing paper. [Means for Solving the Problems] The present invention has been made by intensively studying a flame-retardant backing paper for vinyl wallpaper that does not easily cause blistering (swelling) even at high temperatures during heating during the vinyl paste gelling process. As a result, by using a filler with an oil absorption of 45% or more in the backing paper, there is a significant difference in the occurrence of blisters compared to when using a filler with an oil absorption of less than 45%. They discovered that the above objective could be achieved by incorporating a filler with an oil absorption of 45% or more. Flame-retardant backing paper for wallpaper is obtained by impregnating paper containing filler with a flame retardant using a size press or the like. The filler is used here to improve opacity, which is one of the important qualities of a flame-retardant backing paper for vinyl wallpaper. Generally, titanium dioxide, which has a high specific scattering coefficient, is used because it is easy to obtain opacity. However, titanium dioxide tends to cause blistering. Considering this from the perspective of the small oil absorption of titanium dioxide, it is possible to apply vinyl paste,
It is thought that during gelation, some of the volatile components such as plasticizers and solvents that cannot be absorbed by the backing paper try to come out to the side where the vinyl paste is applied, causing the vinyl layer to swell, causing blisters. It will be done. Therefore, it is thought that a vinyl wallpaper backing paper that has good absorption of volatile matters such as solvents and plasticizers, that is, contains a filler that absorbs a large amount of oil, has excellent blister resistance. The present invention will be explained in more detail. The present inventors created a flame-retardant backing paper for vinyl wallpaper by blending pulp with fillers with different oil absorption amounts and impregnating it with a flame retardant.
Coat to a film thickness of 250μm and heat at specified temperature.
It was dried by heating for 90 seconds and the degree of blistering was observed. As a result, light calcium carbonate (68% oil absorption),
Materials with high oil absorption, such as aluminum hydroxide (55-75% oil absorption) and calcined clay (128% oil absorption), had excellent blister resistance. On the other hand, those with poor blister resistance include rutile titanium dioxide (oil absorption 35%) and anatase titanium dioxide (oil absorption 40%).
%), talc (40% oil absorption), and those without fillers. In addition, here, in calcined clay (oil absorption 128%), which has a particularly high oil absorption,
Even when the filler content in paper was set to 2.0%, it showed far superior blister resistance compared to rutile-type titanium dioxide (40% oil absorption, 10% filler content in paper). From the above, it can be seen that flame-retardant backing paper for vinyl wallpaper containing a filler with a high oil absorption, specifically, a filler with an oil absorption of 45% or more, has excellent blister resistance. Regarding the filler content in the paper, if there is no filler, the blister resistance will be poor, but if a filler with a large amount of oil absorption is used, the blister resistance will be excellent even with a small filler content in the paper. A similar effect can be obtained when a filler with high oil absorption is used in combination. Good results can be obtained by using calcined clay alone with an oil absorption of 128% at 2.0%, or by using a mixture of other fillers with low oil absorption. Therefore, the blending amount of filler with oil absorption of 45% or more was set to 2.0% or more. Note that the fillers with high oil absorption shown here are not limited to these. [Function] The flame-retardant backing paper for wallpaper obtained according to the present invention has excellent blister resistance. Compared to conventional filler-free products or titanium dioxide-containing products, this product uses fillers with high oil absorption (e.g., light calcium carbonate, aluminum hydroxide, calcined clay), and has far superior blister resistance. A flame-retardant backing paper for vinyl wallpaper with high properties is obtained. [Example] Hereinafter, the present invention will be specifically explained with reference to Examples. However, the present invention is not limited thereto. Example 1 Pulp: N-BKP50%, L-BKP40
%, GP10% was beaten and prepared to a freeness of 500ml, and sulfuric acid bandate was added as an internal chemical.
1.0% (addition rate to pulp), wet paper strength enhancer (manufactured by Arakawa Chemical Co., Ltd., trade name, ARAFIX 100) 0.2
% (addition rate relative to pulp), and light calcium carbonate (oil absorption 68%) was added as an internal filler so that the filler rate in the paper was 10%. On this sheet,
A sample was prepared by impregnating a predetermined amount of diguanidine sulfamate (GSA) as a flame retardant (the amount required to obtain disaster prevention grade 2 as specified in JIS A 1322). Here, the basis weight of the sample was set to 70 g/m ² . This sample was used to evaluate blister resistance. Blister resistance was evaluated by applying vinyl paste to a film thickness of 250μm, heating it at the specified temperature (190℃, 200℃, 220℃) for 90 seconds, and observing the degree of blistering.◎ 〇×3
I gave a graded evaluation. The results are shown in Table 1. Examples 2 and 3 Similar to Example 1, aluminum hydroxide (oil absorption 55%, average particle size 1.0 μm) was used instead of light calcium carbonate as the filler (Example 2). Aluminum hydroxide (oil absorption 75%, average particle size 0.5μm)
(Example 3). The results are shown in Table 1. Example 4 Similar to Example 1, the filler was replaced with light calcium carbonate and calcined clay (oil absorption 128%) was used.
The filler ratio in the paper was set to 2% (Example 4). The results are shown in Table 1. Comparative Examples 1, 2, 3 Similar to Example 1, the filler was replaced with light calcium carbonate and anatase titanium dioxide (oil absorption 40
%) (Comparative Example 1). Talc (oil absorption amount
40%) (Comparative Example 2). No filler added (Comparative Example 3). The results are shown in Table 1.

〔Effect of the invention〕

As can be seen from Table 1, the flame-retardant backing paper for vinyl wallpaper of the example containing a filler with a high oil absorption amount has excellent blister resistance. In addition, it can be seen that those containing particularly high oil absorption fillers have excellent blister resistance even with a low filler content in the paper.

Claims (1)

[Claims] 1. Filler with an oil absorption of 45% or more is 2.0% in the paper.
A flame-retardant backing paper for vinyl wallpaper with good blister resistance that is formulated with the above ingredients and treated with a flame retardant. 2. The flame-retardant backing paper for vinyl wallpaper with good blister resistance according to claim 1, wherein the filler is a filler alone or a mixture of fillers having an oil absorption of 45% or more. 3. The flame-retardant backing paper for vinyl wallpaper with good blister resistance according to claim 1 or 2, wherein one or more of light calcium carbonate, aluminum hydroxide, and calcined clay is used as a filler.