JP4874753B2 - Sanitary thin paper - Google Patents

Description

  The present invention relates to sanitary thin paper, and is particularly suitable as a sanitary thin paper for kitchens called kitchen paper or cooking paper.

The cooking paper is used for wiping off moisture and oil on ingredients and tableware, wiping off scattered seasonings, blotting excess oil such as fried food, and squeezing oil after use. In such applications, it is required to quickly absorb and retain moisture and oil, to retain a large amount of moisture and the like, and to have high tensile strength during drying, water absorption and oil absorption. In addition, softness is also very important so that it can be used for draining soft ingredients such as tofu and vegetables, wiping complex dishes, or kitchens.
As for kitchen paper and cooking paper, there are relatively few proposals compared to many commercially available products, and Patent Document 1 is known as a laminated type. Moreover, there exists a thing disclosed in patent document 2 as a cleaning sheet.
However, in Patent Document 1, a pulp layer is interposed between outer layers mainly composed of rayon fibers, and is excellent in that the shape does not easily collapse when absorbing moisture and oil. Since it is mainly composed of fibers, its water absorption and oil absorption properties are not sufficient.
JP 2005-34617 A JP 2002-369882 A

  Therefore, the main subject of this invention is providing the sanitary thin paper which is excellent in water absorption and oil-absorbing property, and does not lose a shape when absorbing a water | moisture content or oil.

The present invention that has solved the above-described problems and the effects thereof are as follows.
<Invention of Claim 1>
An intermediate layer which is a chemical fiber layer substantially entirely composed of heat-bonded binder fibers;
One outer layer which is a chemical fiber mixed pulp fiber layer containing 25 to 50% by weight of a chemical fiber as a proportion containing a binder,
The other outer layer, which is a 100% pulp layer that has been wet creped;
The sanitary thin paper is characterized in that the layers are joined and integrated by heat sealing.

(Function and effect)
In the present invention, a 100% pulp layer is positioned as the outer layer. Accordingly, the water absorption and oil absorption are superior to those of Patent Document 1. However, when both outer layers are made of 100% pulp (which is common in many commercial products), the shape will be lost when the moisture and oil are absorbed (the area is reduced and the bulk is lost). To lose.
Therefore, in the present invention, as the other outer layer, the chemical fiber is a chemical fiber mixed pulp fiber layer containing 25 to 50% by weight of a binder , and the entire intermediate layer is a chemical fiber layer, and the layers are bonded to each other. And integrated. As a result, it becomes difficult to lose its shape when it absorbs moisture or oil.

An adhesive may be used for the integration of the layers, but it is not desirable for food hygiene when used in contact with food. Further, it is possible to join by the airlaid method or the mechanical entanglement method (spun lace method), but there are problems such as excessive increase in rigidity and insufficient joining strength. On the other hand, if it joins using the heat-welding property of a chemical fiber by heat sealing, it is safe in terms of food hygiene, the joining strength is high, and the rigidity is not excessively increased.
Moreover, bulkiness increases further by creping the pulp layer. Creping is creped at a doctor installed on a press roll in the wet part or on a cylinder-type dryer in the dryer part. There are cases of creping with a wet part and creping with a dry part, and the former is distinguished from wet creping and the latter from dry creping. In the case of tissue paper, the emphasis is usually on dry creping, but wet creping can keep the shape of the crepe almost intact even when wet, and its paper elongation is large and flexible. When the oil is absorbed, the shape is difficult to collapse and the bulkiness can be maintained.

<Invention of Claim 2 >
The sanitary thin paper according to claim 1, wherein the integration is performed by heat seal embossing that presses in a dotted pattern.

(Function and effect)
According to heat seal embossing, joining is possible while ensuring bulkiness (enhancing water absorption and oil absorption).

  According to the present invention, if necessary, it is possible to provide a sanitary thin paper sheet that is excellent in water absorbability and oil absorbency and that is not easily deformed when absorbing moisture and oil.

The present invention will be further described below with reference to embodiments.
As shown in FIG. 1, the present invention is a chemical fiber mixed pulp fiber substantially containing the chemical fiber layer 30 as an intermediate layer and a chemical fiber as one outer layer in a proportion of 25 to 50 wt% as a ratio including a binder. It has a layer 20 and a pulp layer 10 of 100% pulp as the other outer layer, and the layers are joined and integrated.

  It is desirable that the joining and integration be performed by heat sealing, particularly heat sealing embossing that presses in the form of dots. The pulp layer is preferably subjected to wet creping.

  As the pulp layer 10, pulp used for normal sanitary thin paper can be used. Preferably, the pulp constituting the pulp layer is preferably composed of pure pulp containing no filler, and is also referred to as NBKP (N material or conifer pulp) rather than LBKP (also referred to as L material or hardwood pulp). ) Is used. In general, NBKP is thicker than LBKP, so the larger NBKP is, the more bulky, the better the water absorbency and oil absorbency attached to the front and back surfaces of the web layer, and the retention of moisture and oil content. It becomes good.

As one outer layer 20 of the present invention, a chemical fiber mixed pulp fiber layer containing 25 to 50% by weight of a chemical fiber as a ratio including a binder is used. Among chemical fibers, it is desirable to use rayon fibers which are soft and excellent in touch feeling and have hydrophilic properties. In particular, those containing 20 to 30% by weight of rayon fibers are desirable, and further, those containing 5 to 10% by weight of vinylon binder fibers are desirable for bonding the rayon fibers to each other. The vinylon binder fiber has a fiber thickness of 1.0 to 5.0 dtex and a fiber length of 2 to 5 mm. Therefore, it is desirable that the chemical fiber in the outer layer 20 of the present invention contains 25 to 40% by weight in the case of rayon fiber. The rayon fiber preferably has a fiber thickness of 1.0 to 5.0 dtex and a fiber length of 2.5 to 5 mm. Thus, a product having excellent flexibility and good water absorption can be obtained. The remaining portion other than the chemical fibers of the outer layer 20 is preferably composed of pure pulp that does not contain a filler, and is also referred to as NBKP (N material or conifer craft pulp) rather than LBKP (also referred to as L material or hardwood kraft pulp). .) Is used. In general, NBKP is thicker than LBKP, so the larger NBKP is, the more bulky, the better the water absorbency and oil absorbency attached to the front and back surfaces of the web layer, and the retention of moisture and oil content. It becomes good.

  More desirably, PP (polypropylene) fiber or PET (polyethylene terephthalate) fiber may be contained in an amount of 20 to 30% by weight instead of the rayon fiber. The PP fiber or PET fiber has a fiber thickness of 1.0 to 5.0 dtex and a fiber length of 2 to 5 mm. As the binder fiber, it is desirable to contain 10 to 20% by weight of a composite binder fiber having a core-sheath structure using a resin having a melting point lower than that of the core part in the sheath part. For example, core / sheath = PP / PP, PP / PE and the like can be mentioned. Moreover, the heat-fusible binder fiber mentioned later can also be used as a binder fiber. Therefore, in the outer layer 20 of this invention, it means that PP fiber or PET fiber and a binder fiber contain 30 to 50 weight%.

  The inclusion of PP fiber or PET fiber instead of rayon fiber has the advantage that it is difficult to lose its shape when it absorbs moisture and oil, and has the advantage of maintaining bulkiness, and compared PP fiber and PET fiber. In some cases, PET fibers are desirable. Since the PET fiber has lipophilicity, the oil absorbability is further improved, and the moisture / oil retained once in the pulp layer is difficult to ooze out again and the moisture / oil retention is improved. In addition, about the remainder other than the chemical fiber of the outer layer 20, it is comprised with the pure pulp which does not contain a filler similarly to the above-mentioned.

  The intermediate layer 30 has a chemical fiber blending ratio at least lower than that of the outer layer 20 and is substantially entirely made of chemical fibers, particularly heat-fusible binder fibers, preferably PP binder fibers or PE binder fibers, more preferably PP binder fibers. is there. These have a fiber thickness of 1.0 to 5.0 dtex and a fiber length of 2 to 5 mm. The above-mentioned composite binder fiber having a core-sheath structure can also be used.

Pulp layer 10 and outer layer 20, the total basis weight of the intermediate layer 30 is desirably a 15 to 60 g / m ^2. Preferably a 40 to 50 g / m ^2. If it is less than 15 g / m ² , the water absorption and oil absorption properties are difficult to improve, and it is difficult to maintain bulkiness. If it exceeds 60 g / m ² , it becomes difficult to develop softness.

  Moreover, the ratio of the rice tsubo of each layer to the total tsubo is preferably pulp layer 10: intermediate layer 30: outer layer 20 = 40-50: 5-10: 40-55. As it absorbs moisture and oil, it becomes difficult to collapse while exhibiting water absorbency and oil absorbency.

  As a heat sealing mode, a known technique and apparatus such as a steel-rubber method or a steel-steel method can be used. In the case of the steel-rubber method, the rubber side is made of a Teflon-containing material to prevent the rubber itself from being melted by heat, and when bonding each layer of sanitary thin paper, only the desired part is sealed (heat fusion) Can be sealed).

  The heat seal is preferably a partial seal by embossing, and the shape of the embossing can be a polygon such as a rectangle, a square, or a rhombus, or a figure such as a star, a flower, or a leaf. . Within this range, the sanitary thin paper sheet itself is soft and feels good when used.

  The area to be embossed may be 10 to 30% per area of one surface of the sanitary thin paper, and if it is less than 10%, the layers of the sanitary thin paper may be insufficiently bonded and easily peeled off. . On the other hand, if it exceeds 30%, the bulk of the sanitary thin paper itself is reduced, and it feels hard when it is held in the hand, and water absorbency and oil absorbency cannot be fully exhibited.

(Test Example 1)
Next, Test Example 1 of the present invention is shown.
Tests were conducted on tensile strength, softness, water absorption, oil absorption, water absorption rate, and oil absorption rate for the examples and comparative examples. Details of physical properties and the like for the examples and comparative examples are shown in Tables 1 and 2 together with the results of each test. The test items and evaluation criteria are as follows.

The raw materials in each test are
Rayon fiber: fiber length 4 mm, fiber thickness 4.0 dtex
PP fiber: fiber length 5 mm, fiber thickness 3.0 dtex
PET fiber: 3 mm fiber length, 3.5 dtex fiber thickness
Vinylon binder fiber: 3mm, fiber thickness 3.0dtex
PP / PP composite binder fiber: 5 mm, fiber thickness 3.0 dtex
PP / PE composite binder fiber: 5mm, fiber thickness 3.0dtex
PP binder fiber: 5 mm, fiber thickness 4.0 dtex
PE binder fiber: 5 mm, fiber thickness 4.0 dtex
What was adjusted to was used.

(Tensile strength)
According to JIS L 1076, it measured about the vertical direction and the horizontal direction. The sample was strip-shaped with a width of 50 mm and a length of 15 cm, and was measured by pulling in the length direction. For cooking paper use, the vertical direction is 45 N / 50 mm or more and the horizontal direction is 13 N / 50 mm or more, so that the vertical direction is 45 N / 50 mm or more, ○ is less than 45 N / 50 mm, and the horizontal direction is 13 N / 50 mm or more. The thing was evaluated as (circle) and the thing less than 13N / 50mm as x.

(soft)
It measured using the testing machine (Automated pure bending test machine, KESFB2-AUTO-A: Kato Tech Co., Ltd. product) which measures rigidity. The evaluation was based on the bending stiffness per unit width expressed as an index of 10 ⁻² · gfcm ² / cm. For cooking paper use, it is preferably less than 15 in the vertical direction and 25 or more in the horizontal direction. Therefore, less than 15 in the vertical direction, x for 15 or more, ○ for 25 or more in the horizontal direction, less than 25 Things were rated as x.

(Water absorption speed)
10 cc water was placed on the sample with a pipette, and the time until the sample completely soaked was measured. It was judged visually whether it soaked or not. In the cooking paper application, it is desirable that the water absorption rate is less than 1.5 seconds, so that less than 1.5 seconds was evaluated as ◯, and 1.5 seconds or more was evaluated as ×.

(Oil absorption speed)
A 10 cc salad oil was placed on the sample with a pipette, and the time until it completely soaked into the sheet was measured. It was judged visually whether it soaked or not. In cooking paper use, since it is desirable that the oil absorption speed is less than 8.5 seconds, the less than 8.5 seconds were evaluated as ◯, and 8.5 seconds or more were evaluated as ×.

(Water absorption)
A sample cut in a 10 cm square is placed on a net, and the sample is floated in a container containing water together with the net. After the water has sufficiently penetrated, the sample is pulled up and left for 30 seconds, and the weight of the sample is measured. A value obtained by subtracting the weight of the sample at the time of drying from the measured weight is defined as a water absorption amount. In the use of the cooking paper, a water absorption amount of 620 g or more is preferable, so that 620 g or more was evaluated as ○, and less than 620 g was evaluated as ×.

(Oil absorption)
A sample cut in a 10 cm square is placed on a net, and the sample is floated in a container containing salad oil together with the net. After the salad oil has sufficiently penetrated, the sample is pulled up and left for 30 seconds, and then the weight of the sample is measured. The oil absorption is a value obtained by subtracting the weight of the sample at the time of drying from the measured weight. In the use of cooking paper, oil absorption amount of 620 g or more is preferable, so that 620 g or more was evaluated as ◯, and less than 620 g was evaluated as ×.

(Comprehensive evaluation)
In all the above evaluation results, for the test examples (examples) evaluated as “◯”, the overall evaluation was “◯”. For the other test examples (comparative examples), the overall evaluation was x.

  As described above in detail, according to the present invention, there is provided a cooking paper that is excellent in water absorption, oil absorption, water absorption / oil absorption retention, tensile strength at the time of water absorption, etc., and has a higher usability in a kitchen. .

  INDUSTRIAL APPLICABILITY The present invention can be used for wiping paper for oil and moisture such as cooking paper and kitchen paper.

It is a schematic diagram of the layer structure of the present invention. It is a schematic sectional drawing of the sanitary thin paper which provided the heat seal emboss.

  10 ... Pulp layer (outer layer), 20 ... Outer layer, 30 ... Intermediate layer

Claims (2)

An intermediate layer which is a chemical fiber layer substantially entirely composed of heat-bonded binder fibers;
One outer layer which is a chemical fiber mixed pulp fiber layer containing 25 to 50% by weight of a chemical fiber as a proportion containing a binder,
The other outer layer, which is a 100% pulp layer that has been wet creped;
The sanitary thin paper is characterized in that the layers are joined and integrated by heat sealing.   The sanitary thin paper according to claim 1, wherein the integration is performed by heat seal embossing that presses in a dotted pattern.

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