TECHNICAL FIELD

The present disclosure relates to methods of manufacturing a microchannel chip and, in particularly, to methods of manufacturing a resin microchannel chip.

BACKGROUND

Recently, microchannel chips (chips having microchannels or reactors on the order of micrometers in size formed utilizing microprocessing techniques) have been used in various fields, including DNA testing, biological material analysis, drug discovery/pharmaceutical development, organic synthesis, and water quality analysis.

Resin microchannel chips, which can be manufactured at low costs, have attracted attention.

Resin microchannel chips are manufactured by joining together a resin substrate having microchannels formed on at least one side thereof and a resin lid substrate that serves as a lid material. Specifically, resin microchannel chips are manufactured by thermo-compression bonding of a resin substrate having microchannels formed thereon and a resin lid substrate by means of a press machine or a roll machine, optionally after applying surface treatment on joining surfaces of the resin substrate and resin lid substrate (see, e.g., PTLS 1 and 2).

CITATION LIST

Patent Literature

PTL 1: JP2011-214838A

PTL 2: JP2006-187730A

SUMMARY

Technical Problem

However, the conventional manufacturing methods using a press machine or a roll machine may not be able to provide a sufficient joint strength in an initial stage after manufacture. Further, the conventional manufacturing methods have a drawback of causing deformation of microchannels during joining when the pressure at the time of pressing or rolling is increased in order to obtain sufficient joint strength.

An object of the present disclosure is therefore to provide a method of manufacturing a microchannel chip, which enables manufacture of a resin microchannel chip with excellent initial joint strength after manufacture and limited deformation of microchannels.

Solution to Problem

The inventor has made extensive studies to solve the foregoing problem and established that it is possible to sufficiently increase the initial joint strength after manufacture while limiting deformation of microchannels when substrates are pressurized using a fluid or an elastic body having a durometer hardness equal to or less than a specific value. The inventor thus completed the present disclosure.

Specifically, the present disclosure aims to advantageously solve the foregoing problem, and a disclosed method of manufacturing a microchannel chip is a method of manufacturing a microchannel chip by joining together a resin channel substrate having microchannels formed on at least one side thereof and a resin lid substrate, the method including: a step (A) wherein surface modification treatment is applied on joining surfaces of the channel substrate and the lid substrate; and a step (B) wherein, after the step (A), the joining surfaces of the channel substrate and the lid substrate are mated and the channel substrate and the lid substrate are pressurized under heating via a fluid or an elastic body having a durometer hardness of E20 or less. By joining together the channel substrate and the lid substrate by pressurizing under heating via a fluid or an elastic body having a durometer hardness of E20 or less after applying surface modification treatment on the joining surfaces in this way, it is possible to sufficiently increase the initial joint strength after manufacture while limiting deformation of microchannels.

“Durometer hardness” herein can be measured using a type E durometer in accordance with JIS K6253.

In the disclosed method of manufacturing a microchannel chip, it is preferred that the channel substrate and the lid substrate are made of cyclic olefin resin. Using such a channel substrate and a lid substrate, it is possible to obtain a microchannel chip having excellent durability.

In the disclosed method of manufacturing a microchannel chip, it is preferred that, in the step (A), the surface modification treatment is applied using a silane coupling agent. When a silane coupling agent is used, it is possible to allow the channel substrate and the lid substrate to be favorably joined together, so that the initial joint strength after manufacture can be further increased. Moreover, when a silane coupling agent is used, it is possible to increase the optical stability of the manufactured microchannel chip compared to a case where surface modification treatment is applied utilizing UV irradiation or other method.

In the disclosed method of manufacturing a microchannel chip, it is preferred that, in the step (B), an autoclave is used to pressurize the channel substrate and the lid substrate via the fluid. When the channel substrate and the lid substrate are pressurized via a fluid using an autoclave, it is possible to allow the channel substrate and the lid substrate to be favorably joined together, so that limitation of deformation of microchannels and improvement of the initial joint strength after manufacture can be achieved at high levels.

In the disclosed method of manufacturing a microchannel chip, it is preferred that, in the step (B), the channel substrate and the lid substrate, placed on top of each other, are accommodated in a bag, the interior of the bag is depressurized and hermetically sealed, the channel substrate and the lid substrate hermitically sealed within the bag are placed in an autoclave, and the channel substrate and the lid substrate are pressurized via the fluid. When the channel substrate and the lid substrate accommodated in a bag are pressurized using a fluid, it is possible to limit degradation of the channel substrate and the lid substrate due to contact with the fluid. Further, when the channel substrate and the lid substrate are pressurized using a fluid after depressurizing and hermitically sealing the interior of the bag containing the channel substrate and the lid substrate, it is possible to allow the channel substrate and the lid substrate to be favorably joined together, so that the initial joint strength after manufacture can be further increased.

When the channel substrate and the lid substrate are accommodated in a bag and then the interior of the bag is depressurized and hermitically sealed in the step (B), it is particularly preferred that, in the step (A), the surface modification treatment is applied using a silane coupling agent. When a silane coupling agent is used, the condensation reaction and/or addition reaction of the silane coupling agent proceed favorably during depressurization in the step (B), allowing the channel substrate and the lid substrate to be further favorably joined together.

Advantageous Effect

According to the present disclosure, it is possible to manufacture a resin microchannel chip with excellent initial joint strength after manufacture and limited deformation of microchannels.

