JPH0576440B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing a writing instrument shaft equipped with a non-slip member.

Conventionally, various synthetic resins have been used as a rubber-like skin layer to prevent slipping of writing instrument shafts, but the surface is too smooth or rough, and the feel to the touch is not necessarily good.

It is an object of the present invention to solve this problem of preventing the writing instrument shaft from slipping. That is, as described below, the present invention has a hard vinyl chloride 18 on the substrate portion 2 of the writing instrument shaft, and a soft vinyl chloride 19 with a high degree of polymerization surrounding it, which is integrally extruded, and the soft vinyl chloride 19 is non-slip. The present invention provides an apparatus for manufacturing a writing instrument shaft whose surface is foamed with a pear-forming activator. The non-slip surface of the writing instrument shaft produced by the apparatus of the present invention has the characteristic that it leaves bubbles on its surface and becomes faded, giving it a good feel and a tasteful design.

Examples of the present invention will be described below.

FIGS. 1 and 2 show a writing instrument shaft 1 manufactured by the apparatus of the present invention. 2 is a substrate portion formed of hard vinyl chloride 18 covered with a rubber-like anti-slip layer 3;
3 is a rubber-like anti-slip layer made of soft vinyl chloride 19 with a high degree of polymerization.

The writing instrument shaft manufacturing apparatus of the present invention will be described below.

In FIG. 3, reference numeral 11 denotes a first extrusion molding machine, which extrudes hard vinyl chloride 18 that forms the substrate portion 2 of the writing instrument shaft 1. 12 is a second extrusion molding machine that extrudes the soft vinyl chloride 19 forming the rubber-like anti-slip layer 3 into the converging annular passage 14b. 13 is a gear pump that delivers an activator for forming a pear base such as a higher alcohol. The activator for forming a pear texture sent out by the gear pump 13 is heated to 100°C by a heater h, and enters the die 14 from the activator for forming a pear texture delivery path 15 into the annular passage 15a for the activator for forming a pear texture.
It merges with the die extrusion path 14a. 16 is a sizing gate, 17 is cooling water, 18 is hard vinyl chloride as described above, 19 is also soft vinyl chloride, and 20 is an inner diameter regulating mold.

That is, the present invention is an apparatus for producing a writing instrument shaft in which a substrate portion 2 is made of hard vinyl chloride 18, and the substrate portion 2 is covered with a soft vinyl chloride 19 having a high degree of polymerization to form a rubber-like anti-slip layer 3. A first extruder 11 extrudes hard vinyl chloride 18, and a second extruder 11 extrudes soft vinyl chloride 19 with a high degree of polymerization.
It incorporates an extrusion molding machine 12, a pear-forming activator delivery path 15 for sending out a pear-forming activator, and a die extrusion path 14a, a hard vinyl chloride 18 is covered with a soft vinyl chloride 19, and , soft vinyl chloride 19
It consists of a die 14 for extruding a hollow laminate whose surface is coated with a "bubble tail" of a pear-forming activator, and a device for externally cooling the extruded hollow laminate; The path 14a has a merging annular passage 14b that joins the hard vinyl chloride 18 and the soft vinyl chloride 19, and a pear-forming active agent sent from the pear-forming activator delivery path 15 downstream thereof. It is provided with an annular passage 15a of an activator for forming a pear-shaped base, which is sprinkled on the soft vinyl chloride 19 in a boiling state.

Next, its effect will be explained.

A hard vinyl chloride 18 for forming the substrate portion 2 of the writing instrument shaft 1 is extruded from a first extruder 11, and a soft vinyl chloride 19 for forming a rubber-like anti-slip layer 3 is extruded from a second extruder 12. .
Then, the two are combined in the converging annular passage 14b of the extruder 14a of the die 14 to form two layers, and in the annular passage 15a of the activator for forming the pear crust, a polyhydric alcohol, such as Unilube (trade name), which is an activator for forming the pear crust, is used. is sprinkled on the outer periphery of the soft vinyl chloride 19 in a boiling state. and soft vinyl chloride 1
9 has a “foam residue” on the surface. So-called “pear ground”
becomes. In other words, the boiling point of polyhydric alcohol, which is an activator for pear crust formation, varies depending on the number of molecules, but is approximately
150°C, and the die temperature is 190° to 200°C, so in order to increase fluidity in advance, a heater h outside the die 14 is used.
The pear-shaped activator heated to around 100° C. boils in the pear-shaped activator annular passage 15a.

In order to prevent this "foam residue" from disappearing in the straight section after being extruded from the die 14, it is necessary to use soft vinyl chloride with a high degree of polymerization.

In other words, in order to provide a non-slip surface with a rough surface and a resilient feel when held in the hand, it is necessary to use a soft vinyl chloride with a high degree of polymerization.

(Reason for using soft vinyl chloride for the rubber-like anti-slip layer and hard vinyl chloride for the substrate portion) The reason why soft vinyl chloride was selected as the rubber-like anti-slip layer 3 in the present invention will be explained below.

The following points can be considered as conditions for using the rubber-like anti-slip layer.

Not easy to slip.

It should be non-sticky, easy to hold, and won't hurt your fingertips.

The epidermal layer does not shift relative to the substrate part 2 even if it is strongly pressed against the paper surface when writing.

The rubber-like anti-slip layer 3 and the substrate portion 2 should not be separated by hand oil or the like.

Even if you put it in a tray made of styrofoam, etc., do not allow it to get scratched.

Therefore, the following properties are required of the material used for the anti-slip layer.

(a) It should be soft and have a slightly rough surface.

(b) Sufficient softness. This is because the anti-slip layer is thin, so if it is a little soft, it will have little effect. In the experimental results, the hardness
It was not effective unless it was softer than 70th grade. It is also necessary to have the ability to recover from dents when pressed.

C. During manufacturing, as shown in FIG. 3, patterns such as surface roughness and leather grain are formed in the converging annular passage 15a inside the die 14, but in the straight part after exiting the die 14, It must be made of a material that will not cause the pattern or grain to come off, such as soft vinyl chloride with a high degree of polymerization.

Furthermore, if other high-temperature melting substances, such as fluorine powder, are mixed into the soft vinyl chloride with a high degree of polymerization, which is the material of the rubber-like anti-slip layer 3, it will cause "slip" as shown in Figure 4. ” is formed, and the surface unevenness pattern x shows a more subtle change y.

FIG. 4 shows the state of the pear ground when no fluorine powder is mixed.

Next, the following points can be considered as the performance of the material of the substrate portion 2.

When selecting the material for the substrate portion 2 of the outer shaft based on the above considerations, it should be easy to extrude, have low moisture permeability when used in felt-tip pens, etc., and have good thread cutting properties. It is as follows.

First, when comparing polystyrene, hard vinyl chloride, and olefin resins in terms of moisture permeability, polystyrene is not suitable.

Secondly, olefin resins are not suitable for processability such as thread cutting.

In this way, hard vinyl chloride remains at the end.

For example, if a writing instrument shaft with a rubber-like non-slip layer made of hard vinyl chloride and soft vinyl chloride with good adhesive properties is made using the manufacturing equipment shown in Fig. 3,
Soft vinyl chloride with a high degree of polymerization satisfies all the performance requirements for the rubber-like anti-slip layer. Other polystyrene and olefin resins are difficult to erase, and satisfactory results cannot be obtained due to surface roughness and the like.

For the above reasons, hard vinyl chloride was selected for the substrate portion 2, and soft vinyl chloride with a high degree of polymerization was selected for the rubber-like anti-slip layer 3.

(Operations and Effects of the Present Invention) First, after the hard vinyl chloride 18 constituting the substrate portion 2 and the soft vinyl chloride 19 with a high degree of polymerization constituting the rubber-like anti-slip layer 3 are bonded and integrated within the die 14. Since the outer periphery of the soft vinyl chloride 19 having a high degree of polymerization is sprinkled with a boiling activator for forming a pear-shaped base, a pear-shaped base can be formed simultaneously with extrusion molding within the die 14. That is, since the pear-shaped activator annular passage 15a is provided, the pear-shaped part can be formed while continuing extrusion of the extruded product extruded into the extrusion passage 14a.

Since the rubber-like anti-slip layer 3 is made of soft vinyl chloride with a high degree of polymerization, it can be erased and has a good feel as an anti-slip layer.

The hard vinyl chloride of the substrate portion 2 has low water permeability, is easy to cut into strips, and has strong adhesive strength with the soft vinyl chloride 19 of the rubber-like anti-slip layer 3.

[Brief explanation of the drawing]

FIG. 1: A perspective view of a writing instrument manufactured by the apparatus of the present invention, FIG. 2: A cross-sectional view taken from FIG. Figure 4: Shows the condition of pear ground when fluorine powder is mixed. Figure 4: Shows the state of the pear ground when no fluorine powder is mixed. (Figures 1 and 2), 1... Writing instrument shaft, 2... Substrate portion, 3... Rubber-like anti-slip layer, (Figure 3), 11... First extrusion molding machine, 12...
...Second extrusion molding machine, 13...Gear pump for delivering active agent for forming pear base, 14...Dice, 14a...
Extrusion path, 14b... Merging annular path, 15... Active agent delivery path for pear-shaped formation, 15a... Active agent annular path for forming pear-shaped area, 16... Sizing gate, 1
7... Cooling water, 18... Hard vinyl chloride for the outer cylinder, 19... Soft vinyl chloride for the rubber-like anti-slip layer, 20... Inner diameter regulating mold, x... Uneven pattern,
y...Subtle change.

Claims (1)

[Scope of Claims] 1. A writing instrument in which a substrate portion 2 is made of hard vinyl chloride 18, and the substrate portion 2 is covered with a highly polymerized soft vinyl chloride 19 that serves as a non-slip member, thereby forming a rubber-like anti-slip layer 3. The shaft manufacturing device includes a first extruder 11 that extrudes hard vinyl chloride 18, and a second extruder 11 that extrudes soft vinyl chloride 19 with a high degree of polymerization.
It incorporates an extrusion molding machine 12, a pear-forming activator delivery path 15 for sending out a pear-forming activator, and a die extrusion path 14a, a hard vinyl chloride 18 is covered with a soft vinyl chloride 19, and , a die 14 for extruding a hollow laminate whose surface is coated with a "bubble tail" of a pear-forming activator on the surface of soft vinyl chloride 19, and a device for cooling the extruded hollow laminate from the outside. The die extrusion path 14a of the die 14 has a merging annular passage 14b for merging the hard vinyl chloride 18 and soft vinyl chloride 19, and a pear-forming passage 14b, which is fed from the pear-forming activator delivery path 15, on the downstream side thereof. An apparatus for manufacturing a writing instrument shaft equipped with a non-slip device, which is equipped with an annular passageway 15a for forming an active agent for forming a pear-shaped surface, in which a forming active agent is sprinkled in a boiling state on soft vinyl chloride 19.