JPS60212707A - Method and device for manufacturing synthetic resin optical transmitting body - Google Patents

Abstract

PURPOSE:To manufacture continuously the titled optical transmitting body by a stable wire diameter, by measuring a diameter of an organic base material extruded continuously from a forming means, and adjusting a feed quantity of a pre-polymer based on a measured value. CONSTITUTION:A cylinder 19 to which transparent glass windows 14, 15 for measuring a wire diameter of an organic base material have been installed is inserted between a diffusion layer 18 and a forming tool 12. A laser light emitting part 7 and a laser photodetecting part 6 are installed on both sides of this cylinder 19 with a window, so that a laser light 8 scans in the direction crossing the organic base material 21 through the window 14 by a tuning fork. The light 8 which has transmitted through the base material 21 is detected by the photodetecting part 6, and based on the time when the photodetecting quantity has been reduced during the scan, namely, the time of scan which has transmitted through the base material 21, its diameter is calculated. It is fed back to a driving voltage of an extruding motor 4, and an extruding speed of a piston 2 is controlled in order to align the wire diameter of the organic base material with a set value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a synthetic resin optical transmission body having a refractive index distribution that changes with distance from a central axis, and an apparatus KfJ4 used therein.

[Technical background of the invention]

A transparent rod-like body whose refractive index distribution is expressed by the following formula (1) exhibits a convex lens action, and a light beam traveling through this round-shaped body meanderes along the central axis. The period is expressed by the following equation (2). Here, no is the refractive index on the central axis, n(r) is the refractive index at a point located at a distance 1111 of r from the central axis, and A is a positive constant (refractive index distribution constant).

n(r)-no(l-//2Ar2) fl)L-jπ
/f), (2) When the refractive index distribution is expressed by the following equation (3), a concave lens effect is exhibited. Here, B is a positive constant (refractive index distribution constant).

n(r)-'no(/+//, 2Br2) (31 When molding the above-mentioned organic matrix, first, a monomer Ma that produces a reticular polymer pa having a refractive index Na is prepolymerized to obtain plasticity. General formula expressing flow % Formula % (4) (In the formula, shear rate is shear rate, α is shear stress, K is the reciprocal of plastic viscosity, and n is a constant.) The value of n at 20'C at K is A viscous fluid exhibiting plastic flow with a value of 10 or more (
(hereinafter referred to as prepolymer fluid) is obtained. Next, this prepolymer fluid is put into an extrusion device, and a constant voltage is applied to the piston moving motor of the extrusion device to continuously extrude the prepolymer fluid, which is then supplied to a molding device and heated while moving through a passage in the molding device. The organic matrix is obtained by polymerization.

By diffusing the monomer Mb that forms a polymer having a refractive index different from that of the organic matrix KMa through the surface of the organic matrix in a liquid phase or gas phase, or by polymerizing it at the same time as the diffusion, the refractive index can be changed. It is possible to manufacture a synthetic resin light transmitting body that changes continuously from the surface to the inside.

The method for continuously manufacturing synthetic resin optical transmitters as described above was first disclosed in Japanese Patent Application No. 55-/2062. , Tokugansho! ;l
'-/20t2&, the present inventors have proposed in Japanese Patent Application No. 31-/20A27. However, this method has the following problems. In other words, the extrusion device is composed of a cylinder and a piston, but it is impossible to reduce the pitch error of the feed screw and the speed error of the motor to 0, and there is a limit to the amount of K required to move the piston at a constant speed. .

Furthermore, there is a limit to the accuracy of the inner diameter of the cylinder, and it is expected that there will be variations.

Therefore, the volume velocity of the prepolymer fluid extruded from the extrusion device is difficult to be constant.

Furthermore, since this prepolymer fluid is heated and polymerized to form an organic matrix, the volume changes and the rate of change is not always constant.

For this reason, the stability of the volumetric velocity of the above-mentioned organic base material 1 is further reduced. Since the above organic matrix is stretched at a constant speed, if there is a change in the volumetric velocity of the organic matrix over time,
The change in diameter of the organic matrix becomes K.

Furthermore, if the monomer Mb, which forms a polymer having a refractive index different from that of the Ma polymer, is diffused into the base material while the diameter of the organic base material remains variable, the refractive index distribution will also change. become.

From the above, in order to continuously manufacture synthetic resin optical transmitters with constant quality, first of all, in order to stabilize the diameter of the organic base material,
Must be controlled.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned drawbacks of the prior art and provide a method for continuously manufacturing the synthetic resin optical transmission body with a stable wire diameter, and an apparatus used therefor.

[Summary of the invention]

The method of the present invention achieves the above objects by pumping a prepolymer fluid into a molding means, and continuously extracting an organic matrix from the molding means in a state that retains its shape and allows the diffusion of additives therein. The extruded organic matrix is passed through a diffusion means and a heating means in succession, wherein the diffusion means diffuses the additive into the organic matrix, and the heating means diffuses the additive into the organic matrix. In a method for manufacturing a synthetic resin light transmitting body in which the distribution of the additive in the organic base material is fixed by heating the organic base material, the diameter of the organic base material continuously extruded from the molding means is The gist is to control the diameter of the organic base material by determining I1m near the exit of the molding means and adjusting the amount of prepolymer fed to the molding means based on the measured value.

Further, the present invention provides a suitable apparatus for carrying out the above method,
An extrusion device that pumps prepolymer fluid to a molding means and extrudes the molded base material; and an extrusion device that molds the prepolymer fluid supplied from the extrusion device and extrudes the molded base material; An apparatus for manufacturing a synthetic resin optical transmission body is provided, which includes a base material diameter measuring device that measures the diameter of a base material, and a control device that controls the amount of prepolymer fluid discharged from the extrusion device in accordance with a diameter measurement signal.

〔Example〕

Hereinafter, an embodiment of the method for manufacturing a synthetic resin optical transmission body according to the present invention and an apparatus using the same pressure will be explained with reference to the drawings. In FIG. 1, a cylinder ( 1) contains a prepolymer fluid (30) that is used as a raw material for synthetic resin optical transmission bodies.
The prepolymer fluid (30) can be pumped into the supply pipe (9) by means of a piston (K). Further, as shown in FIG. 2, this piston (2) is moved by an extrusion motor (4)K via a single feed screw (J/).

Next, a forming tool (7
, 2) is formed with a through hole (3) having a diameter slightly larger than the outer diameter of the supply pipe (q) mentioned above, and inside this through hole (3) there is a further hole K. (3) A molded tube (13) made of a Teflon tube of the same diameter is attached. The prepolymer fluid (30) pushed out from the supply pipe (W) passes through this Teflon tube (/3). In addition, the above molding tool (/
2) A temperature gradient is provided at the upper and lower parts of the jacket (12) through which relatively high-temperature hot water passes, so that the temperature gradually increases from the lower part to the upper part.

Above the molding tool (/2) is a diffusion tube (/2) as a diffusion means.
I), and the cylindrical organic base material (21) formed by the forming tool (/2) VC has this diffusion tube <iB
A predetermined diffusion is performed within the area.

Between this diffusion tube (/Ir) and the forming tool (12), there is a transparent glass window (H0° (/
! The circular tube (/9) to which ;) is attached is inserted. λ windows (hat>I<m are the organic matrix (2
1) are installed parallel to each other with the parts in between.

On both sides of this windowed circular tube (/9), there are laser emitting parts (7).
, a laser light receiving section (6) is installed 1, and a laser light receiving section (6) is installed.
lr) is the organic matrix (21) through the window (c) with a tuning fork.
) is designed to scan in the direction across.

Light transmitted through the base material (2/) lIl! (za) is the light receiving part (≦
), and its diameter is calculated based on the time during which the amount of light received decreases during scanning, that is, the scanning time during which the light passes through the base material (2/).

This laser light receiving section (≦) is connected to a wire diameter controller D)rc, and the deviation between the measured value of the wire diameter of the organic base material and the set value is sent to the wire diameter controller<S). Then, a control signal is calculated based on this input signal, and the extrusion motor (41
) to control the extrusion speed of the piston (2) in order to adjust the wire diameter of the organic base material to the set value.

The base material (21) that is continuously extruded from the molding tool (/J) by the pressing force of the piston (2) has shape retention properties and is in a state where additives can be diffused into the base material (21). The base material (21) exiting the forming tool (12) is then passed through a diffusion tube (l).
Enter the Into this diffusion tube (/J), monomer Mb, which forms a polymer having a different refractive index from the polymer of monomer Ma constituting the base material, is supplied in a gas phase or liquid phase. There is. This monomer Mb diffuses from the surface of the base material (21) to the inside, and a distribution is formed in the base material in which the concentration of Mb gradually decreases from the surface toward the center.

The base material (2/) leaving the diffusion tube (/za) is then passed through the heating tube (20
), where it is heated and polymerization proceeds, fixing the distribution of the monomer Hb diffused into the base material.

The base material (21), which has almost completed its polymerization while passing through the heating 11 (20), is pulled out by a pull-out roller (#) + (/7) and cut into a predetermined length by a cutting device (not shown).

The cut base material, which has a refractive index distribution inside, can be used for lenses, optical transmission fibers, etc. by polishing both ends, or it can be heated and stretched to make the diameter thinner and then subjected to the above treatment to be used for lenses, optical transmission fibers, etc. used.

The monomer (4a) to be the raw material of the transparent gel body as the organic matrix in the above examples is a monomer having two or more types of groups selected from the group consisting of an allyl group, an atarylic acid group, a methacrylic acid group, and a vinyl group. mer can be used. Next, specific examples of monomer Ha will be given.

(1) Allyl compound 7 Diallyl esters such as diallyl talate, diallyl isophthalate, sialyl terephthalate, diethylene glycol bisallyl carbonate: triallyl trimellitate,
Triallyl esters such as triallyl phosphate and triallyl phosphite: Unsaturated acid allyl esters such as allyl methacrylate and allyl acrylate.

(2) The compound R1 and R3 represented by Rl-R2-R3 are both a vinyl group, an acrylic group, a vinyl ester group, or a methacrylic group (1 compound; either one of R1 and R3 is a vinyl group, an acrylic group) , a methacrylic group and a vinyl ester group,
A compound where the other is any of the remaining three groups.

Here, R2 can be selected from the divalent groups shown below.

■ O- OHg -(OHgOHgO)m-OH20H2-(m-0-2
0)\0H2-CI(2/ -(OHg)p-(P=J~/U (OH2)in -0H2-0-OH2-(1,j-/to3)(OH2)
jH OHs 0H3 (3), a mixture of the above fl) and (2) monomers, or at least /al of the five types of monovinyl compounds, vinyl esters, acrylic esters and methacrylic esters and the above ( A mixture of 1) or (2) with a monomer (or a mixture thereof).

Furthermore, examples of the monomer Mb include the following.

(4), 0I (compound represented by 2-G-GOOY, where X is a hydrogen atom or a methyl group, -(OH2)l
H(j-/-1), 1-propyl group, i-butyl group,
S-butyl group, t-butyl group, and C1+ OH20B
20 -OH20H3(P-/~t) A group selected from the group consisting of -(OF2), F(a-/
-4), -0RB(OFg)bH(b-/~l),-
0H20H20-OH2GF3, (CI(20H20
) COFgOF2H (0-/ ~+), -OH20H20-OHg(CFg)aF (a-/
~G), OHg(CFg)do(OFg)jF(d-/
~J, l-/-4) and -f31(002H5)s.

(5), OH2-Cj HOO-R4 compound 1, where R4 is -(OH2) f-OHs (f-
o-, 2), (OHg)gill (g-' to 3), represents a group selected from the group.

(61, +41 and (5) monomer mixture.

Any of the above (1) to (3) as the monomer Ma and (4) and (6) as the monomer Hb can be combined.

In addition, in order to adjust the gelation state of the transparent gel object,
As mentioned in section (3), the method of adding a crosslinking monomer MaK monomer having one unsaturated group and CBr4. CCl
4. A method of adding a chain transfer agent such as mercaptans, or a method of using both in combination is effective.

[Test example]

Next, an example of controlling the organic base material using the method and control device for controlling the wire diameter of the organic base material in the production of a synthetic resin optical transmission body according to the present invention will be described.

Diethylene glycol bisallyl carbonate (OR) in which 3.0% by weight of benzoyl peroxide (BPO) was dissolved
-j9) was prepolymerized by heating at 73''C for 63 minutes to prepare a prepolymer fluid.

This ° prepolymer fluid has a viscosity of approximately 1000 CpB (
It is a viscous fluid in which the value of n in the Kiku equation is n-820 at (0°C).This prepolymer fluid is
)K insert, diameter passing through the forming tool (3)<zmm,
14 in a Teflon tube (13) of length roomm,
It was continuously fed at a constant flow rate of JX/(7-2 mj/min).

The upper jacket pipe (//) K of the above forming tool (lλ) is 7
There is hot water in J”C, and S in the lower jacket pipe (10).
1°C hot water is flowing through each molding tool (/2), and a temperature gradient is created in which the temperature gradually increases from the bottom to the top of the molding tool (/2). Above Teflon tube (13)
During the 170 minute passage through the tube, the prepolymer fluid gelled and formed into an organic matrix approximately 41 mm in diameter.

This organic matrix consists of acetone-insoluble components, network structure polymers), acetone-soluble, methanol-insoluble components (!I-type polymers, 5% by weight, acetone-soluble, methanol-soluble components (monomer), It consisted of 70% by weight.

Rollers for pulling up this organic base material (8<), (/7)
o, at a constant speed of 52 cm/min through the diffusion tube (
7g).

The e-Me laser (output/mW) (output/mW) is emitted from the laser emitting part through the window (C0, (lj)) of the circular tube (19) into this organic base material.
The wire diameter is measured by scanning f with a tuning fork and capturing the change in the amount of light received by the light receiving section.

The wire diameter measuring device generates a deviation output in proportion to the deviation between the measured value of the wire diameter of the organic base material and the set value. This deviation output is sent to the wire diameter controller (,t)K, performs PID control calculation, and determines the drive voltage to be sent to the extrusion motor (4'). In this case, the coefficients of P, I, and D were set to 30%+7 minutes and 0.1 minutes.

By performing the above feedbank control operation, the deviation of the wire diameter of the organic base material is set to the set value? , ±60 for 00mm
Improved from μm to ±SμmK. Furthermore, the present invention provides a method and a control device for controlling the wire diameter of an organic base material in the production of deviations in diameter of synthetic resin light transmitters that are produced as products after completion of polymerization and come out of pulling rollers (#) and (/7). Accordingly, it is possible to continuously manufacture an organic base material with a uniform wire diameter, and in turn, it is possible to stably and continuously manufacture a synthetic resin transmission body having a uniform diameter and optical performance.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an example of an apparatus for carrying out the present invention;
FIG. 2 is an enlarged view of the main parts of the apparatus shown in FIG. 1. In addition, in the symbols used in the drawings, (1) cylinder (2) piston (3) through hole (4) extrusion motor (51, Ij diameter feed roller (6) laser light receiving part (
7) Laser emitting part (8) Laser light (9) Supply pipe
(10), (11) Hot water jacket pipe (12) Forming tool (13) Forming pipe (t4) M diameter itl constant Jt [(15) ls diameter measuring window (16) Lifting motor (17) Lifting motor ( 1st) Diffusion tube (19) Circular tube with window (20) Heat treatment tube (21) Feed screw. I+ Do l JP-A-Sho GO-212707 (6) Figure 2

Claims (2)

[Claims] (1) A state in which the prepolymer fluid can be pumped into a molding means, retaining its shape, and allowing additives to diffuse therein, etc.
An organic matrix is continuously extruded from the forming means, and the continuously extruded organic matrix is continuously passed through a diffusion means and a heating means, and at this time, the organic matrix is added to the organic matrix by the diffusion means. In the method for manufacturing a synthetic resin optical transmitter, the method comprises: diffusing the additive and fixing the distribution of the additive in the organic base material by heating the organic base material using the heating means; The diameter of the extruded organic matrix material is measured near the exit of the forming means,
A method for manufacturing a synthetic resin optical transmission body, characterized in that the diameter of the organic base material W is controlled by adjusting the amount of prepolymer fed to the molding means based on the measured value. (2) An extrusion device that pumps the prepolymer fluid to the molding means and extrudes the molded base material, a molding device that molds the prepolymer fluid supplied from the extrusion device, and the diameter of the base material molded by the molding device. 1. An apparatus for manufacturing a synthetic resin optical transmission body, comprising: a base material diameter determination device for measuring the diameter of a base material; and a control device for controlling the amount of prepolymer fluid discharged from the extrusion device in accordance with a diameter measurement signal.